Mother Tongue • Issue XXVI • 2025 • pp. 149–160

Revisiting Greek ἄχθος

Gregory Haynes

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The etymology of Greek ἄχθος, ἄχθομαι ‘burden, to be loaded, to be vexed’ is uncertain. It has been compared to Hittite ḫatk- ‘to shut, to close,’ with derivatives appearing to connote ‘tight, pressing.’ Its analysis as a disyllabic root, *h₂edʰgʰ-e-, is also problematic since PIE roots were, in most cases, monosyllabic. The present paper will consider the possibility that Greek ἄχθος is a compound consisting of two separate PIE roots, one of which is *dʰéĝʰ- ‘earth’ as attested in Greek χθών.

Homer and Hesiod’s use of ἄχθος ‘burden, weight’

1. “Telemachus, no man is more unlucky in his guests than you, seeing that you keep such a filthy vagabond as this man here, always wanting bread and wine, and skilled neither in the works of peace nor those of war, but a mere burden on the earth.”1

The Greek phrase here translated as “… burden on the earth” is ἄχθος ἀρούρης, where ἀρούρης is literally ‘arable land.’2

2. “They pelted us from the cliffs with rocks huge as a man could lift, and at once there rose throughout the ships a dreadful din…”3

The phrase here translated as “huge as a man could lift” is ἀνδραχθέσι. LSJ glosses this word as “loading a man, as much as a man can carry.”4

3. “And as when a shepherd easily carries the fleece of a ram, taking it in one hand, and but little does its weight burden him, so Hector lifted up the stone and carried it…”5

Here “little does its weight burden him” translates ὀλίγον τέ μιν ἄχθος ἐπείγει.

4. “He carried a mighty weight of dry wood…”6

This translates φέρε δ’ ὄβριμον ἄχθος ὕλης ἀζαλέης…

5. “… it is bad if you put too great a load on your wagon and break the axle…”7

“put too great a load on your wagon” translates ἐπ’ ἄμαξαν ὑπέρβιον ἄχθος ἀείρας.

Homer, Hesiod, and later authors also employed ἄχθος, ἄχθομαι and related forms to indicate the concepts: hated, vexed, pained, or grieved, but these uses are considered to be metaphorical derivations by Chantraine (2009: 143–144). With respect to both nominal and verbal forms of this Greek word, Frisk (1960: 200–201) considers them “nicht sicher erklärt.”

Modern Lexicographers

Risch (1964: 78) proposed an etymological connection between Greek ἄχθομαι and Hittite ḫatk- ‘to shut, to close.’ This has been accepted by Puhvel, Beekes, Kloekhorst, and LIV (doubtfully).8 Beekes suggests that the semantic value ‘shut’ in Hittite must have arisen from the original concept, ‘to squeeze.’ The proposed root is * h₂edʰgʰ-, which Kloekhorst calls an “awkward looking form.” The vast majority (perhaps originally all) of PIE roots are monosyllabic and this, along with the semantic divergence, raises questions about the etymological correspondence.9

An Alternative Analysis based on PIE *dʰéĝʰ- ‘earth’

Alternatively, ἄχθος could be considered an ancient compound ἄ-χθος. The second half of this compound would then be parallel to Grk. χθών ‘earth, ground, land,’ a reflex of PIE *dʰéĝʰ-om-, *dʰĝʰ-om- ‘earth, ground, man (as earth worker), slave’ as seen in the following cognates: Hit tēkan ‘earth, ground,’ Ved kṣám- ‘earth, ground,’ Skt kṣa ‘field, protector or cultivator of a field, peasant,’ Lat humus ‘earth,’ homo ‘human being,’ OE guma ‘man, (bride)groom,’ Lith žēmė ‘earth,’ OCS zemlja ‘earth, land,’ Phrygian zemel ‘slave,’ TochA tkaṃ ‘earth, ground,’ Alb dhe (from *dʰgʰ-em-) ‘earth.’10

As is well-known, this root often appears in radical metathesis form (with inversion in the ordering of root consonants) and often is attested in zero grade (as in the Greek and Vedic).

If such a compound form was originally a Greek construction, the initial element of ἄ-χθος would either be the well-known alpha-copulative signifying ‘with, together with’11 or else an assimilated form of Grk. ἄγω ‘drive, lead, carry.’12

If the first, this would then signify ‘with earth,’ and would originally have been applied to commoners or slaves tasked with carrying loads of earth, clay, mud, or stones for construction projects, indicating that they were loaded, weighed down, burdened. From here it is not difficult to imagine the semantic shift to vexed, pained, or grieved, since those emotions would be a natural outcome of being burdened with heavy loads and worked to one’s extreme limits.

If the second case is the correct one, then the compound would be ἄγ-χθ-ος, where the gamma was assimilated to the following chi, signifying: carrying earth → loaded, burdened.

On the other hand, if ἄ-χθος reflects an ancient PIE rather than a later Greek compound, then the two possibilities would be the following:

1) PIE *sm̥- or som- as attested in Lat sem- ‘at the same time, together,’ OHG samn ‘together,’ Lith sam- ‘with,’ OCS so- ‘with,’ Av ha(m)- ‘together,’ Skt sam- ‘with,’ Grk ‘with, together with.’13

Plus: PIE *dʰéĝʰ- *dʰgʰ- ‘earth, ground, land’ as attested in the previously listed examples.

yielding:

*sm̥-dʰgʰ- or (in metathesis form) *sm̥-ĝʰdʰ- → Grk ἄ-χθ-ος ‘with earth, weighted, loaded.’

Or, if the first element of the PIE compound was an assimilated form of *h₂eĝ- ‘lead, carry, drive’ (instead of *sm̥- as above), then the components would be:

2) PIE *h₂eĝ- ‘lead, carry, drive’ as seen in the following PIE cognates: Lat agō; Grk ἄγω ‘lead, carry, fetch, bring; Ved ájati ‘to drive’; Arm acem ‘leads,’ OIr -aig, -agat ‘drive, lead,’ tāin (from *to-ag-no) ‘raid,’ ON aka ‘go, travel, drive,’ MIr āg ‘fight, warrior’s ardor,’ TochAB āk- ‘lead, guide, drive,’ āśäm ‘lead.’14

Plus: PIE *dʰéĝʰ- *dʰgʰ- ‘earth, ground, land’ as described above

yielding (with metathesis):

*h₂eĝ-ĝʰdʰ- (then with assimilation) → *h₂e-ĝʰdʰ- → Grk ἄ-χθ-ος ‘carrying earth, weighted, loaded.’

A third (more remote) possibility is that the initial in ἄ-χθ-ομαι is a prothetic vowel15 parallel to Grk. χθές ‘yesterday’ and ἐχθές ‘yesterday,’ in which case the meaning of ἄχθομαι would be simply ‘to be earthed → to be weighed down with earth.’

Cognate with Hittite?

If either of the above cases is correct, then it could not be possible for Hittite ḫatk- ‘shut, close’ to be cognate with Grk ἄ-χθ-ος for the following reasons:

What about the goddess Ἀχθεία ?

Hesychius defines Ἀχθεία as ἡ Δημήτηρ, μυστικῶς ‘Demeter, according to the mysteries.’ Since Demeter is typically taken as “Mother Earth,” this would confirm a link between the word ἄχθος and the concept Earth. The second element of Δημήτηρ is obviously ‘mother.’ The first is thought by some as a pre-Greek word for ‘earth,’ and by others as Illyrian (attested by Alb. dhe ‘earth’) and therefore a cognate of Grk χθών, arising from PIE *dʰĝʰ- ‘earth, ground, land.’16

Additional Evidence from the Sanskrit

As mentioned above, PIE *dʰgʰ-em became Ved kṣám-, Skt kṣā́ ‘earth, ground.’ The initial and final consonants of this zero-grade root (via an intermediate Proto-Indo-Iranian dźh-) fused to become Skt kṣ as in kṣám- and in a number of other derivatives, not all of which are typically viewed as being based on the root *dʰgʰ-. The following are a few such instances (with comments):

1. kṣmā́ ‘the earth,’ kṣmā́tala ‘the surface of the earth,’ kṣā́ma ‘ground, earth.’17

These are straightforward attestations of PIE *dʰgʰ-em.

2. kṣa ‘field, protector or cultivator of a field, peasant’18
3. kṣoṇá ‘a multitude of men, people (as opposed to the chief), kṣoṇi ‘the earth,’ kṣoṇimaya ‘containing or representing the earth,’ kṣauṇī ‘the earth,’ kṣauṇītala ‘the surface of the earth.’19

In an earlier article (Haynes 2023: 106–109) I have argued that attestations of PIE *dʰĝʰ-em with the semantic value ‘man’ (Lat homo ‘human being,’ Goth guma ‘man,’ Phrygian zemel ‘slave’), as well as another root of the same consonantal form, *dʰ—ĝʰ- (i.e., *dʰeu̯ĝʰ-, with the Greek attestation τυγχάνω carrying as one of its meanings ‘common, or vulgar men’), refer not to men in general, but rather to men of a lower class, i.e., earth workers, cultivators of the soil, or builders employing earth, stones, mud, or clay. The preceding two Sanskrit forms: kṣa ‘cultivator of a field, peasant’ and kṣoṇá ‘a multitude of men, people (as opposed to the chief)’ clearly fit into the same rubric. These terms do not refer to the rulers or chiefs, but rather to the commoners and slaves. According to the ancient logic: they are low, they are dirty, they are dirt.

4. kṣétra ‘landed property, land, soil, field, place region, country, enclosed plot of ground,’ kṣétrakara ‘cultivating a field,’ kṣétrakarṣaka ‘soil-plougher, husbandman,’ kṣétraja ‘produced in a field,’ kṣétrajeṣá ‘contest for landed property, acquisition of land,’ kṣétratā ‘seat, place of residence,’ kṣétrapati ‘owner of a field, land owner, landlord, farmer,’ kṣétrasāti ‘acquisition of fields or land,’ kṣatrá ‘dominion, supremacy, power, might,’ kṣatríya, ‘governing, endowed with sovereignty, dominion, supremacy, power, might, the second or military caste.’20

KEWA expresses uncertainty as to the etymology of these terms, as does EWAia. I would argue that the derivation from *dʰĝʰ- is very likely, considering the many references to ‘earth, land, soil, field, plot of ground, cultivation, plowing, acquisition of land, possession of land, lordship over lands and countries.

5. kṣubh, kṣubhita, kṣubdha, kṣobha, kṣóbhaṇa, kṣobhya ‘shake, tremble, be agitated or disturbed, be unsteady, stumble, cause to shake, stir up, excite, frightened, alarmed, angry, enraged, causing emotion’21
6. kṣip ‘to utter abusive words, insult, revile, abuse.’22

The semantic values of these two Sanskrit terms are directly parallel to those derivations of Grk ἄχθομαι and ἄχθος that have been glossed as: ‘mental oppression, to be hated, vexed, pained, or grieved; burden, trouble; burdensome, oppressive; annoyance, suffering; vexed at being conquered, etc.’23 I would argue that these are compound roots based on PIE *dʰĝʰ- as the first element with some root containing a strong labial consonantal component as the second.

7. kṣi ‘possess, have power over, rule, govern, be master of,’ kṣi ‘abide, stay, dwell, reside, inhabit,’ kṣití ‘dwelling, habitation, house, the earth, soil of the earth, settlements, colonies, nations,’ kṣitija ‘earth-born, produced of or in the earth, son of the earth, daughter of the earth,’ kṣitítrāṇa ‘protection of the earth’ kṣitídhārin carrying soil or earth,’ kṣitípati ‘lord of the earth,’24

These Skt words are typically ascribed to the PIE roots *tḱ-ei̯- and *te-tḱ-. In that previously mentioned earlier article (Haynes 2023: 107–108) I have argued that these two PIE roots:

1. *tḱ-ei̯- ‘cultivate soil, settle a land, dwell in a place’

Ved kṣéti ‘dwells, lingers,’ Myc ki-ti-je-si = /ktiⁱensi/ ‘to build on, cultivate, or work land,’ Lat pōnō ‘put, place, sit down,’ Grk κτίσις ‘settlement,’ κτίζω ‘people a country and build houses and cities in it,’ Av šiti ‘settlement,’ Arm šēn ‘dwell, build on, farm, town.’25

and

2. *teḱ-s, *te-tḱ- ‘establish, produce, hew, cut, fabricate, fashion, axe’

Lith tašýti ‘hew, trim,’ OCS tesati ‘hew,’ Skt tákṣati ‘fashions, creates, carpenters, cuts,’ Grk τέκτων ‘architect,’ τέχνη ‘art, craft, skill, technique,’ Hit taksanzi ‘undertake, prepare, cause, joint,’ OHG dehsa ‘axe.’26

are de-voiced and de-asperated variants of PIE *dʰĝʰ-, showing phonetic development similar to that which occurred in Tocharian. The first shows a clear connection to the earth: ‘settling, building, and dwelling on land; cultivating and farming the ground.’ The second refers fundamentally to the practice of building with earth as the basic material of walls and houses constructed of mud bricks. Later, builders began using wood and other materials, but the term for building (originally working with stones, mud, and clay) was later applied to other materials and techniques.

Examples of this phonetic reduction (loss of voicing and aspiration) were given in that earlier article. The part of the introduction of that article that describes this process is reproduced below by way of example, but many more instances are given there.

Phonetic Reduction

Another type of root mutation could be called reduction. This concept is also familiar, since something very close to it is seen in Tocharian (and to some extent in Hittite) where the rich PIE obstruent inventory has been reduced to include only the simple, unvoiced, unaspirated (lenis) forms.27 It has been suggested that this change may have been due to the influence of a substrate language with a similarly limited range of obstruents.28 This same dynamic can be seen in distinct synonymous PIE roots. Obvious examples are often remarked upon in the standard handbooks. The following are some examples of this transformation:

*gol(H)u̯os ‘bare, bald’*kl̥Hu̯os ‘bald’29
*-dʰro-, *dʰlo- = instr. suffix*-tro-, *-tlo- = instr. suffix30
*h₂eng- ‘bend’*h₂enk- ‘bend’31
*peh₂ĝ- ‘fasten securely’*peh₂ḱ- ‘fasten securely’32
*pei̯ĝ- ‘draw, color’*pei̯ḱ- ‘draw, color’33
*sredʰ- ‘boil, be agitated, move’*sret- ‘boil, be agitated, move noisily’34
*bʰendʰ-ŕros ‘relation’*pent-h₂ros ‘father-in-law’35
*h₂eu̯g- ‘increase, become strong’*h₂eu̯k-s- ‘grow, become large’36
*greh₂bʰ- ‘hornbeam’*karp- ‘hornbeam’37
*gʰabʰ- ‘take, seize’*kap- ‘have, hold, seize’38
*pleh₂g- ‘strike, beat’*pleh₂k- ‘strike, beat’39
*ḱu̯oi̯dis ‘white’*ḱu̯oi̯tós ‘white’40
*sab- ‘sap’*sap- ‘sap’41
*stei̯b- ‘make stiff’*stei̯p- ‘make stiff’42
*dei̯ĝ- ‘teach, show, indicate’*deiḱ- ‘preach, say, index’43
*u̯ei̯bʰ- ‘vibrate, be agitated’*u̯ei̯p- ‘move back and forth, vibrate’44
*gʰebʰōl ‘head’*kapolo- ‘head’45
* ĝʰr̥d- ‘heart’*ḱérd- ‘heart’46

Many more examples of this dynamic can be observed once the variation of medial resonants in PIE roots is allowed for. The evidence suggests that an ancient dialectical subset of PIE speakers experienced a phonetic influence similar to that which occurred in Tocharian, and then, during a later period of reunification with a group that had not experienced this linguistic change, the dialects became merged. The result is that, after this merger, synonymous pairs (doublets) coexisted within the basic vocabulary of PIE and these have persisted down into the various daughter languages. These synonyms are now considered separate roots, but they should, it will be argued, be seen as variants of an ancient original.

In their most strict formulation, these phonetic reductions can be summarized as follows:

d, dʰbecamet
b, bʰbecamep
ĝ, ĝʰbecameḱ,
g, gʰbecamek
gᵘ, gᵘʰbecamek or kᵘ

The semantic parallels of *teḱ-s, *te-tḱ- to the voiced and aspirated form of this root can best be seen by way of comparison to the following, also quoted from that earlier article:

*dʰei̯ĝʰ-, *dʰi̯ĝʰs- ‘form, build, mold mud or clay, knead, smear, plaster; wall of mud’ Skt déhmi ‘spread, fill,’ déhī ‘wall, rampart, dam,’ Goth digan ‘form, fashion, knead, make pottery,’ ON deig ‘dough,’ digr ‘thick,’ NE dough, Lith žiedžiù ‘form from mud,’ TochB tsikale ‘to form,’ Lat fingō, finxī ‘form, shape,’ figūra ‘form, shape, figure,’ fictilis ‘fashion out of clay, made of earth or clay,’ figulus ‘potter,’ Av pairi-daēza- ‘enclosure’ (> NE paradise) Grk τεῖχος, τοῖχος ‘wall, embankment,’ possibly Grk θιγγάνω ‘touch with the hand,’ OIr digen ‘build, firm, solid, hard, strong, fixed.’47

Mallory and Adams (223-224, 371) write, “The underlying semantics of *dheiĝh indicate that it was specifically associated with the working of clay (e.g. Lat fingō ‘fashion,’ Skt déhmi ‘smear, anoint,’ TochAB tsik- ‘fashion [pots, etc.],’ hence the English cognate dough; in Greek and Indo-Iranian it is also associated with building walls, e.g. Av pairi-daēza ‘build a wall around’ … but there are also cognates of more general meaning, e.g. OIr con-utainc ‘builds,’ Lith diežti ‘whip, beat,’ Arm dizanem ‘heap up’.” And in EIEC (629) they write: “The substance from which the walls were made, [earth] came to be applied both to the finished product, e.g., Grk τοῖχος ‘wall,’ Av uz-daēza- ‘wall,’ and clay-like substances, e.g. Germanic dough.

Another probable example of a reduced form of ἄχθος ‘load, burden, mental oppression; vexed, pained, or grieved; burden, trouble,’ can be seen in a Greek word denoting the same semantic field: ἀγανακτέω ‘be indignant or irritated.’ This is a word of uncertain etymology, with Beekes even doubting its source in Greek at all.48 This word could be analyzed as ἀγαν-α-κτέω, with the first element being the familiar Greek adverb ἄγαν ‘much, too much,’ and the remaining compound α-κτέω being a phonetically reduced version of ἄχθος, ἄχθομαι. The original meaning of the compound would therefore be ‘overloaded, overburdened, literally: too much with earth, or carrying too much earth.’

Conclusion

The preponderance of the evidence suggests that Greek ἄχθος, ἄχθομαι is a compound based on the PIE root *dʰeĝʰ- ‘earth, ground, field, earth worker.’

1Homer, Odyssey 20.379, Murray translation, vol. 2, 308–309; see also Iliad 18.104 where the same phrase is repeated.
2Beekes, Etymological Dictionary of Greek, 137.
3Homer, Odyssey 10.121, Murray translation, vol. 1, 366–367.
4LSJ, s.v. ἀνδαχθήσ, 128.
5Homer, Iliad 12.452, Murray translation, vol.1, 588–589.
6Homer, Odyssey 9.233, Murray translation, vol. 1, 332–333.
7Hesiod, Works and Days, 692.
8See Beekes, Etymological Dictionary of Greek, 183; Kloekhorst, Etym. Dict. Of Hittite Inherited Lexicon, 134–135; LIV 255; Puhvel, HED 3, 266f.
9In Haynes (2023:59), I argue that PIE root structure can be generalized as *(s)-C [+/- R (R)] -C-, where (s) is the s-mobile, C is any consonant, and R is any resonant or laryngeal (or a zero-grade of the same), and that apparently disyllabic roots, including any additional element that follows the final consonant of the monosyllabic root, is a root-extension, a derivational ending, a suffix, or the remnant of some ancient compound that will not have been a part of the original root.
10Haynes 2023, Table 17; IEW 414–416; EIEC 174; NIL 86–88; Mallory & Adams 120; Watkins 20; DELG 143; Ringe 19; EDHIL 858–862; Bomhard 145; EIEC 247–248; Illič-Svityč no. 69; Ruhlen and Bengtson 323–326; Fortson 461 (zemel); MW 324; Blažek, Tocharian ‘man’ vs. ‘god’ in Perspective of Semantic Oppositions, 105–145
11Smyth, 250; Beeks 1.
12Beekes 18–19; LSJ 17–18.
13Beeks 1; M&A 291; de Vann 553; IEW 902–905; Blažek, The Prefix *Sm̥-/Som- in the Indo-European Tree- and Plant-Names, 5–11.
14Haynes 2024, Table 7; LIV 255–256; IEW 4–6; LSJ 8, 14, 17–18; OLD 85, 87; Monier-Williams 9; DELG 9, 16; Bosworth and Toller 5 (see LIV 256, n. 3); Mallory and Adams 280, 403; Buck 191; EIEC 201, 284, 348; Frisk I-18, II-348; EWAia 50–52; Beekes 18–19; de Vries 3; Adams 36; Anttila 1ff and Anttila, “Aggression and Sustenance, 121; NIL 267–270; Watkins 1; Bomhard 706–707; Dolgopolsky no. 17.
15Smyth §41, p. 17; LSJ 748, 1991.
16Beekes, 324; see also EIEC, s.v. Earth Goddess, 174; and OCD, s.v. Demeter, 263.
17MW 333; KEWA 288; 295; EWAia 423–425. (Note: MW employs the notation /sh/ to indicate what in modern usage is written /ṣ/. In the list to follow, these will be normalized to /ṣ/.)
18MW 324.
19MW 333.
20MW 332; KEWA 285, 293; EWAia 422, 432.
21MW 331; KEWA 292; EWAia 440 s.v. kṣobh.
22MW 328.
23Beekes 183; MW 296.
24MW 324–328; KEWA 289; EWAia 427, 431
25Beekes 788–789; LIV *tḱei- 643; IEW 626; Watkins 95; Mallory and Adams 223; EIEC 622. Compare possible metathesis form: TochB 2keta ‘parcel of land, estate, field,’ Adams, Dictionary of Tocharian B, 191; and Adams, History and Significance of Some Tocharian B Agricultural Terms, 373.
26LIV *tetḱ- 638; IEW *teḱp- 1058–1059; Watkins 92; Mallory and Adams 220, 243, 283; Bomhard 206; EIEC 139; Beekes 1460; EDHIL 813–814.
27See EIEC 14, 28, 592. See also Kloekhorst, “Chapter 5: Anatolian,” in Thomas Olander, ed., The Indo-European Language Family, 2022, “…the merger of PIE mediae and aspiratae into a single series that is called lenis (PIE*d ,*dʰ > PAnat.*/t/)…” See Hodge, “Indo-European Consonant Ablaut,” 143–162, for an early attempt to systematize some of these features along with a good survey of the prior literature on the subject.
28Peyrot, “The deviant typological profile of the Tocharian branch of Indo-European may be due to Uralic substrate influence,” 72–121.
29EIEC 45; IEW 554.
30EIEC 52; IEW 692; Mallory and Adams 57.
31EIEC 61; IEW 45–46.
32EIEC 64; IEW 787–788.
33EIEC 64; IEW 794–795; LIV 464.
34EIEC 76; IEW 1001–1002.
35EIEC 196; IEW 127; Beekes 1171.
36LIV 274–275, 288–289; EIEC 248; IEW 84–85.
37EIEC 273; de Vaan 94; Mallory and Adams 161.
38EIEC 563; IEW 407–409, 527–528; Watkins, s.v. “kap-” 38.
39LIV 484–485, see 485, n. 1 regarding the original identity of these roots.
40Mallory and Adams 332; Watkins 46; IEW 628–629; see below, Table 19.
41Mallory and Adams 158; IEW 880.
42LIV 592, 594.
43Watkins 15; IEW 188.
44de Vaan 674; IEW 1131; LIV 671.
45See Haynes 2023, Table 18.
46IEW 580; EIEC 262–263; Mallory and Adams; Michael Witzel, “Comparison and Reconstruction,” 48.
47LIV 140; IEW 244; NIL 118; de Vries 194; Mallory & Adams 223–224, 228; Watkins 18; EIEC 283, 649; Bomhard 166.
48Beekes 8.

Abbreviations of Literature

AdamsDouglas Q. Adams, Dictionary of Tocharian B
AHDAmerican Heritage Dictionary
ALEWHock, Wolfgang, Altlitauisches etymologisches Wörterbuch
CLLMelchert, Craig, Cuneiform Luvian Lexicon
DELGChantraine, Pierre, Dictionnaire étymologique de la langue grecque
de Vaande Vaan, Michiel, Etymological Dictionary of Latin & other Italic Languages
EDHILKloekhorst, Alwin, Etymological Dictionary of the Hittite Inherited Lexicon
EIECMallory, James P., and Douglas Q. Adams, Encycl. of Indo-European Culture
EWAiaMayrhofer, Manfred, Etymologisches Wörterbuch des Altindoarischen
IEWPokorny, Julius, Indogermanisches etymologisches Wörterbuch
KEWAMayrhofer, Manfred, Kurzgefaßtes etymologisches Wörterb. des Altindischen
LIVRix, Helmut, Lexicon der indogermanischen Verben. 2nd edition
LSJLiddell, Scott, and Jones, A Greek–English Lexicon
Mallory and AdamsMallory and Adams, The Oxford Introduction to Proto-Indo-European and the Proto-Indo-European World
NILWodtko, Irslinger, and Schneider, Nomina im Indogermanischen Lexikon
OCDOxford Classical Dictionary
OLDOxford Latin Dictionary

References

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Adams, Douglas Quentin. A Dictionary of Tocharian B. Amsterdam: Rodopi, 1999.
Anttila, Raimo. “Aggression and Sustenance: Driving (*ag-) and Beating (*gʷhen-) Symbiosis in (Proto-) Indo-European.” UCLA Indo-European Studies 1, edited by Vyacheslav V. Ivanov and Brent Vine. University of California at Los Angeles, Program in Indo-European Studies, 1999.
Anttila, Raimo. Greek and Indo-European Etymology in Action: Proto-Indo-European *aĝ-. Amsterdam: John Benjamins, 2000.
Beekes, Robert. Etymological Dictionary of Greek. Leiden and Boston: Brill, 2009.
Blažek, Václav. “The Prefix *Sm̥-/Som- in the Indo-European Tree- and Plant-Names.” Studia Minora Facultatis Philosophicae Universitatis Brunensis. A 51, 2003—Linguistica Brunensia.
Blažek, Václav. “Tocharian ‘man’ vs. ‘god’ in Perspective of Semantic Oppositions.” The Journal of Indo-European Studies, Volume 51, Number 1 & 2, Spring/Summer 2023, 105-145.
Bomhard, Allan R. A Comprehensive Introduction to Nostratic Comparative Linguistics: With Special Reference to Indo-European. 4th ed. Charleston, South Carolina, 2021.
Bosworth and Toller. Anglo-Saxon Dictionary. Oxford: Oxford University Press, 1921.
Buck, Carl Darling. A Dictionary of Selected Synonyms in the Principal Indo-European Languages. Chicago: The University of Chicago Press, 1949.
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Abbreviations of Names of Indo-European Languages

AlbAlbanianCornCornish
ArmArmenianCymrCymric
AvAvestanGallGallo-Roman
BretBretonGaulGaulish
BulgBulgarianGothGothic
CLuvCuneiform LuvianGrkGreek
HLuvHieroglyphic LuvianOLatOld Latin
HitHittiteOLithOld Lithuanian
IllyrIllyrianONOld Norse
KhotKhotaneseOPersOld Persian
LatLatinOPrusOld Prussian
LatvLatvianORusOld Russian
LithLithuanianOSaxOld Saxon
LuvLuvianOscOscan
LycLycianOssOssetic
LydLydianOSwedOld Swedish
McymrMiddle CymricOWelsOld Welsh
MEMiddle EnglishPhrygPhrygian
MHGMiddle High GermanPIEProto-Indo-European
MIrMiddle IrishPolPolish
MPersMiddle PersianRusRussian
MWelsMiddle WelshSCSerbo-Croatian
MycMycenaean GreekSktSanskrit
NENew EnglishSlavSlavic
NorwNorwegianSogdSogdian
NPersNew PersianSwedSwedish
NWelsNew WelshTochATocharian A
OAvOld AvestanTochBTocharian B
OCSOld Church SlavonicUkrUkrainian
OEOld EnglishUmbUmbrian
OFrisOld FrisianVedVedic
OHGOld High GermanYAvYoung Avestan
OIrOld Irish