As might be imagined, the PED entry for Dhamma is of considerable length. I have here included much, but have edited back much also. For the full entry, see the PED on line, linked below.

Dhamma: ...[Ved. dharma & dharman, the latter a formation like karman...; dh.r ... to hold, support: that which forms a foundation and upholds = constitution. Cp. Gr. qro/nos, Lat. firmus & fretus; Lith. derme (treaty), cp. also Sk. dhariman form, constitution, perhaps = Lat. forma, E. form] constitution etc.

A. Definitions by Commentators: Bdhgh gives a fourfold meaning of the word dhamma (at DA I.99= DhA I.22), viz. (1) gu¼e (saddo), applied to good conduct; (2) desan¤ya¸, to preaching & moral instruction; (3) pariyattiya¸, to the 9 fold collection of the Buddh. Scriptures (see navanga); (4) nissatte (-nijj¨vate), to cosmic (non-animistic) law.

-- No. 1 is referred to freq. in expls of the term, . . . Another and more adequate fourfold definition by Bdhgh is given in DhsA 38, viz. (1) pariyatti, or doctrine as formulated, (2) hetu, or condition, causal antecedent, (3) gu¼a, or moral quality or action, (4) nissatta-nij¨vat¤, or "the phenomenal" as opposed to "the substantial," "the noumenal," "animistic entity." Here (2) is illustrated by hetumhi ¾¤¼aµ dhammapaÂisambhid¤: "analytic knowledge in dhamma's means insight into condition, causal antecedent"...Since, in the former fourfold definition (2) and (3) really constitute but one main implication considered under the two aspects of Doctrine as taught and Doctrine as formulated, we may interpret Dhamma by the fourfold connotation: -doctrine, right, or righteousness, condition, phenomenon. - For other exegetic definitions see the Coms & the Niddesa, e. g. Nd1 94; for modern expls & analyses see e. g. Rhys Davids, Buddh. India pp. 292-4; Mrs. Rh. Davids, Buddhism (1912) pp. 32 sq., 107 sq., 235 sq.;...

B. Applications and Meaning.

--1. Psychologically; "mentality" as the constitutive element of cognition & of its substratum, the world of phenomena. It is that which is presented as "object" to the imagination & as such has an effect of its own: -- a presentation (Vorstellung), or idea, idea, or purely mental phenomenon as distinguished from a psycho-physical phenomenon, or sensation (re-action of sense-organ to sensestimulus). The mind deals with ideas as the eye deals with forms: it is the abstraction formed by mano, or mind proper, from the objects of sense presented by the sense-organ when reacting to external objects. Thus cakkhu "faculty of sight" corresponds to rupa "relation of form" & mano "faculty of thought" (citta & ceto its organ or instrument or localisation) corresponds to dhamma "mentalized" object or "idea" (Mrs. Rh. D. "mental object in general," also "state of mind")

(a) subjective: mental attitude, thought, idea, philosophy, truth, & its recognition (anubodhi) by the Buddha, i. e. the Dhamma or world wisdom = philosophy of the Buddha as contained & expounded in the Dialogues of the 5 Nikayas...

- Note. The idea of dhamma as the interpreted Order of the World is carried further in the poetical quasi-personification of the Dh. with the phrase "dhammaja dh-nimmita dh-d¤y¤da" (born of the Norm, created by the Norm, heir of the Norm;...). That which the Buddha preached, the Dhamma kat) e)coxh/n, was the order of law of the universe, immanent, eternal, uncreated, not as interpreted by him only, much less invented or decreed by him, but intelligible to a mind of his range, and by him made so to mankind as bodhi: revelation, awakening. The Buddha (like every great philosopher & other Buddhas preceding Gotama: ye pi te ahesu¸ at¨ta¸ addh¤na¸ Arahanto Samm¤sambuddh¤ te pi dhamma¸ yeva sakkatv¤ S I.140) is a discoverer of this order of the Dhamma, this universal logic, philosophy or righteousness ("Norm"), in which the rational & the ethical elements are fused into one. Thus by recognition of the truth the knower becomes the incorporation of the knowable (or the sense of the universe=Dhamma) & therefore a perfect man, one who is "truly enlightened" (samm¤-sambuddha): so Bhagava j¤na¸ j¤n¤ti passa¸ passati cakkhu-bh¬to ¾¤¼a-bh¬to dhamma* brahma* & in this possession of the truth he is not like Brahma, but Brahm¤ himself & the lord of the world as the "master of the Truth": vatt¤ pavatt¤ atthassa ninnet¤ Amatassa d¤t¤ dhammass¤m¨ S IV.94; & similarly "yo kho Dhamma¸ passati so mam passati; yo mam passati so Dhamma¸ passati" = he who sees the Buddha sees the Truth S III.120. Cp. with this also the dhamma-cakka idea (see cpds.). On equation Dhamma=Brahman see esp. Geiger, Dhamma pp. 76-80, where is also discussed the formula Bhagavato putto etc. (with dhammaja for the brahmanic brahmaja). - In later (Abhidhamma) literature the (dogmatic) personification of Dhamma occurs. See e. g. Tikp A 366.

As 6th sense-object "dhamma" is the counterpart of "mano": manas¤ dhamma¾ vi¾¾¤ya "apperceiving presentations with the mind" S IV.185 etc....; mano-vi¾¾eyy¤ dhamm¤ S IV.73; cp. S III.46; IV.3 sq.; V.74; D III.226, 245, 269. Ranged in the same category under the anupassan¤-formula (q. v.) "dhammesu dhamm-¢nupassin" realising the mentality of mental objects or ideas, e. g. D II.95, 100, 299; A I.39, 296; II.256; III.450; IV.301. Also as one of the 6 ta¼has "desire for ideas" D III.244, 280. - As spirituality opposed to materiality in contrast of dh. & amisa: It 98 (*dana: a mat. & a spir. gift).

(b) objective: substratum (of cognition), piece, constituent (=khandha), constitution; phenomenon, thing, "world," cosmic order (as the expression of cosmic sense, as under a & 2). Thus applied to the khandhas: vedan¤dayo tayo kh. DhA I.35 (see Khandha B 3); to r¬pa vedan¤ sa¾¾¤ sankh¤r¤ vi¾¾¤¼a S III.39;=sankh¤r¤ D III.58, 77, 141. Freq. in formula sabbe dhamm¤ anicc¤ (+dukkh¤ anatt¤: see nicca) "the whole of the visible world, all phenomena are evanescent etc." S III.132 sq. & passim. diÂÂhe [va] dhamme in the phenomenal world (opp. sampar¤yika dh. the world beyond): see under diÂÂha (S IV.175, 205 etc.). - ye dhamm¤ hetuppabhav¤ tesa¸ hetu¸ Tath¤gato ¤ha "of all phenomena sprung from a cause the Buddha the cause hath told" Vin I.40 (cp. Is¤ Upanishad 14). lokadhamm¤ things of this world (viz. gain, fame, happiness etc., see under l¤bha) D III.260; Nd2 55. uttari-manussa-dh*¤ transcendental, supernormal phenomena D I.211, cp. D III.4; abbhuta-dh*¤ wonderful signs, portents Miln 8 (tayo acchariy¤ a. dh. p¤turahesu¸); PvA 2: hassa-khiÀÀh¤-rati-dh.-sam¤panna endowed with the qualities or things of mirth, play & enjoyment D I.19; III.31; g¤ma* things or doings of the village D I.4 (cp. DA I.72).

2. Ratio-ethically-

(a) objective: "rationality," anything that is as it should be according to its reason & logicality (as expressed under No. 1 a), i. e. right property, sound condition, norm, propriety, constitution as conforming to No. 1 in universal application i. e. Natural or Cosmic Law . . . In this sense freq. -* as adj.: being constituted, having the inherent quality (as based on Natural Law or the rational constitution of the Universe), destined to be . . ., of the (natural) property of . . ., like (cp. Gr. -eidh/s or E. -able, as in change-able=liable to change, also E. -hood, -ly . . ., with ref. to the Sankharas S IV.216 sq.; in the PaÂiccasamupp¤da S II.60; akkhaya imperishable Pv IV.152 (d¤na¸ a-dh. atthu). cavana* destined to shift to another state of existence D I.18; III.31; It 76; VvA 54. j¤ti-jar¤-mara¼a* under the law of birth, age, & death D III.57; A I.147; III.54; PvA 41 . . ., in formula ya¸ ki¾ci s-dh*¸ sabban tan n-dh*¸ "anything that is destined to come into existence must also cease to exist" D I.110, 180; S IV.47 & passim. . . .

(b) subjective: "morality," right behaviour, righteousness, practice, duty; maxim (cp. Âh¤na), constitution of character as conforming to No. 1 in social application, i. e. Moral Law. - Often in pl.: tenets, convictions, moral habits; & as adj. that which is proper, that which forms the right idea; good, righteous, true; opp. adhamma false, unjust etc.; evil practice
(i) Righteousness etc.: S I.86 (eko dh. one principle of conduct; II.280 (dh. isina¸ dhajo: righteousness is the banner of the Wise); kusala dh. D I.224; dhamme Âhita righteous Vv 168; ¾¤ti* duty against relatives PvA 30; deyya*= d¤na PvA 9, 70; sad* faith (q. v.) - opp. adhamma unrighteousness, sin A II.19; V.73 sq.; D III.70 (*r¤ga+ visama-lobha & micch¤-dhamma); Pv III.96 . . .
(ii) (pl.) Tenets, practices etc.
(aa) good: kusala dh. D II.223, 228; III.49, 56, 82, 102 etc.; S II.206; . . .
(bb) evil: ¤vara¼¨y¤ S IV.104; p¤pak¤ Vin I.8; D I.70; A I.202; akusal¤ D III.56, 57, 73, 91 etc.; lobha*, dosa*, moha* S I.70=It 45=Nd2 420; S I.43; M III.40; . . .
(cc) various: gambhira duddasa etc. Vin I.4; D I.12; S I.136; - Cp. S II.15, 26; Nd2 320; It 22, 24; Ps I.5, 22, 28; Vbh 105, 228, 293 sq. etc. etc.
(iii) (adj.) good, pious, virtuous etc. . . .

C. The Dhamma, i. e. moral philosophy, wisdom, truth as propounded by Gotama Buddha in his discourses & conversations, collected by the compilers of the 5 Nikayas . . ., resting on the deeper meaning of dhamma as expld under B 1 a, & being in short the "doctrinal" portions of the Buddhist TipiÂaka in contradiction to the Vinaya, the portion expounding the rules of the Order (see piÂaka). Dhamma as doctrine is also opposed to Abhidhamma "what follows on the Dhamma." -

1. Dhamma and Vinaya, "wisdom & discipline," as now found in the 2 great Pi?akas of the B. Scriptures, the Vinaya and SuttantaPiÂaka (but the expression "PiÂako" is later. See PiÂaka). . . ., i. e. "the bhikkhus who know the Suttantas, remember the Vinaya & preach the Word of the Buddha" Vin II.75 (I.169), cp. IV.67. . . . one who knows both by heart; . . . Vin II.285 . . .

2. Dhamma, Buddha, Sangha. On the principle expld in Note on B 1 a rests the separation of the personality of the teacher from that which he taught (the "Doctrine," the "Word," the Wisdom or Truth, . . . A person becoming a follower of the B. would conform to his teaching (Dh.) & to the community ("Church"; Sangha) by whom his teaching was handed down. The formula of Initiation or membership is therefore threefold, . . . i. e. I put myself into the shelter of the B., the Dh. & the S. . . .

3. Character of the Dhamma in var. attributes, general phraseology. - The praise of the Dh. is expressed in many phrases, of which only a few of the more frequent can be mentioned here. Among the most famous is that of "dhamma¸ deseti ¤di-kaly¤¼a¸ majjhe-k*, pariyos¤na-k*, etc. "beautiful in the beginning, beautiful in the middle & beautiful in the end," e. g. D I.62; S I.105; IV.315; A II.147, 208; III.113 sq., 135, 262; D III.96, 267; Nd2 316; It 79; VvA 87. It is welcome as a friend, beautifully told, & its blessings are immediate: sv' akkh¤ta, sandiÂÂhika, ak¤lika, ehipassika etc. D II.93; III.5, 39, 45, 102; S I.9, 117; II.199; IV.271; A III.285 etc. . . . It is likened to a splendid palace on a mountain-top Vin I.5=It 33, or to a quiet lake with s¨la as its banks S I.169=183; and it is above age & decay . . . S I.71. Whoever worships the Dh. finds in this worship the highest gratification . . . S I.210; . . .

4. Dhamma and anudhamma. Childers interprets anudhamma with "lesser or inferior dhamma," but the general purport of the Nikaya passages seems to be something like "in conformity with, in logical sequence to the dhamma" i. e. lawfulness, righteousness, reasonableness, truth (see KS II.202; Geiger, Pali Dhamma pp. 115-118). It occurs (always with Dh.) in the foll. contexts: . . ."to explain according to the truth of the Dhamma" D I.161; III.115; Ud 50; . . ."walking in perfect conformity to the Dh." A II.8; . . ."one who has reached the complete righteousness of the Dh." D II.224; III.119; S III.40 sq.; It 81; A III.176 . . .

-cakkhu "the eye of wisdom," perception of the law of change. Freq. in the standing formula at the end of a conversation with the Buddha which leads to the "opening of the eyes" or conversion of the interlocutor, viz. "viraja¸ v¨tamala¸ dh-cakkhu¸ udap¤di" D I.86, 110; II.288; S IV.47; A IV.186; Vin I.11, 16, 40 etc. . . .
-cariy¤ walking in righteousness, righteous living, observance of the Dh., piety . . .S I.101
-d¤na gift of;
-d¤y¤da heir of the Dh.; spiritual heir (cp. above note on B 1 a) D III.84; S II.221; M I.12; III.29; It 101;
-dipa the firm ground or footing of the Dh. (usually combd with atta-dipa: having oneself as one's refuge, self-dependent) D II.100; III.58, 77; S V.154;
-vicaya investigation of doctrine, religious research Dhs 16, 20, 90, 309, 333, 555; Vbh 106; Vism 132;
-sota the ear of the Dh. S II.43.

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