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: (m. & rarely nt.) [Ved. dharma & dharman, the latter a formation like karman (see kamma for expln of subj. & obj. meanings); dh.r (see dh¤reti) 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, . . . DA I.249; . . .PvA 211; . . . VvA 84; No. 3 e. g. also at PvA 2. 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" Vibh 293, and see Niyama (dhamma*). 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.; Dhs. trsl. XXXIII. sq.; and most recently the exhaustive monograph by M. & W. Geiger, Pali Dhamma. Abhandlungen der Bayer. Akademie XXXI. 1; München 1920; which reached the editors too late to be made use of for the Dictionary.

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 worldwisdom=philosophy of the Buddha as contained & expounded in the Dialogues of the 5 Nikayas (see below C.)

- 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; see under cpds. and Dhammata; also s. v. Niyama). 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. (see formula under r¬pa); 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 . . .

-akkhana discussing or preaching of the Dhamma Nd1 91;
-atthadesan¤ interpretation of the Dh. Miln 21;
-¢dhikara¼a a point in the Dh. S IV.63=V.346;
-anuvattin acting in conformity with the moral law Dh 86, cp. DhA II.161;
-¢nus¤rin of righteous living D III.105, 254 (+saddh¤*); M I.226, 479; A I.74; IV.215; IV.23; S V.200; Pug 15; Nett 112, 189;
-anvaya main drift of the faith, general conclusions of the Dh., D II.83= III.100; M II.120;
-abhisamaya understanding of the Truth, conversion to the Dhamma . . .: Pug 41; Miln 20; DhA I.27; IV.64; PvA 31 etc.;
-¢mata the nectar of righteousness or the Dh. Miln 22 . . ., 346;
-¤d¤sa the mirror of the Dhamma D II.93 (name of an aphorism) S V.357 (id.); Th 1, 395; ThA 179;
-¤yatana the field of objects of ideation S II.72; Dhs 58, 66, 147, 397, 572, 594; Vbh 70, 72 sq.;
-¤ramma¼a: dh. as an object of ideation Dhs 146, 157, 365; cp. Dhs. trsl. 2;
-¤r¤ma "one who has the Dh. as his pleasure-ground," one who rejoices in the Dh. A III.431; It 82 (+dh-rata); Sn 327; Dh 364, cp. DhA IV.95;
-¤lapana using the proper address, a fit mode of addressing a person as followed by the right custom. See Dial. I.193-196; J V.418;
-oja the essence or sap of the Dh. S V.162; DhA IV.169;
-osadha the medicine of the Dh. Miln 110, 335.
-kath¤ ethical discussion, fit utterance, conversation about the Dh., advice D III.151; J I.217; VvA 6; PvA 50, 66;
-kathika (adj.) one who converses about ethical problems, one who recites or preaches the Dh., one who speaks fitly or properly. Often in combn. with Vinaya-dhara "one who masters (knows by heart) the Vinaya," & bahussuta "one who has a wide knowledge of tradition": Vin IV.10, 13, 141; A III.78; DhA II.30; also with suttantika "one who is versed in the Suttantas": Vin I.169; II.75; IV.67. The ability to preach the Dh. is the first condition of one who wishes to become perfected in righteousness (see dhamm-¢nudhamma, above C 4): S II.18, 114=III.163; M III.40. - A I.25 sq.; II.138; Pug 42; J I.217; IV.2 (*thera). Cp. also AvS II.81;
-kathikatta (nt.) speaking about the Dh.; preaching M III.40; A I.38 (+vinayadhara-katta);
-kamma a legally valid act, or procedure in accordance with the Rules of the Order Vin IV.37, 136, 232; A I.74 (+vinaya*); a* an illegal act Vin IV.232; A I.74;
-karaka a proper or regulation (standard) water-pot, i. e. a pot with a filter for straining water as it was used by ascetics Vin II.118, 177, 301; J I.395; VI.331; DhA III.290, 452; VvA 220 (not *kara?ena); PvA 185; Miln 68;
-k¤ma a lover of the Dh. D III.267; A V.24, 27, 90, 201; Sn 92.
-k¤ya having a body according to the Norm (the dhammata of bodies). See Bdhgh as translated in Dial. III. ad loc.; having a normal body (sic Bdhgh, esp. of the B. D III.84;
-ketu the standard of the Dh., or Dh. as standard A I.109=III.149;
-khan- dha the (4) main portions or articles of the Dh. (s¨la, sam¤dhi, pa¾¾¤, vimutti) D III.229; cp. Sp. AvS II.155;
-gu one who knows the Dh. (analogous to vedagu) J V.222; VI.261;
-gutta protecting the Dh. or protected by the Dh. (see gutta) S I.222; J V.222 (+dhpala);
-cakka the perfection or supreme harmony of righteousness (see details under cakka), always in phrase dh-cakka¸ pavatteti (of the Buddha) "to proclaim or inaugurate the perfect state or ideal of universal righteousness" Vin I.8=M I.171; Vin I.11; S I.191; III.86; Sn 556, 693; Miln 20, 343; DhA I.4; VvA 165; PvA 2, 67 etc.; besides this also in simile at S I.33 of the car of righteousness;
-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
-c¤rin virtuous, dutiful M I.289; II.188; Dh 168; Miln 19 (+samac¤rin);
-chanda virtuous desire (opp. k¤ma*) DhsA 370; Vbh 208;
-ja born of the Dh. . . .D III.84=S II.221; It 101;
-j¤la "net of the Dh.," name of a discourse . . . D I.46;
-j¨vin living righteously It 108; Dh 24 (=dhammena samena DhA I.239);
-¾¾u one who knows the Dh. J VI.261;
-ÂÂha standing in the Law, just, righteous S I.33 (+s¨lasampanna); Sn 749; J III.334; IV.211; ThA 244, -ÂÂhita=*ÂÂha D I.190;
-ÂÂhiti* having a footing in the Dh. S II.60, 124, cp. *ÂÂhitata: establishing of causes and effects S II.25;
-takka right reasoning Sn 1107 (=sammasankappa Nd2 318);
-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;
-desan¤ moral instruction, exposition of the Dh. Vin I.16; D I.110 etc. (see desan¤);
-dessin a hater of the Dh. Sn 92;
-dhara (adj.) one who knows the Dh. . . .
-dh¤tu the mental object considered as irreducible element Dhs 58, 67, 147 etc.; Vbh 87, 89 (see above B 1); an ultimate principle of the Dh., the cosmic law D II.8; M I.396; S II.143 sq.; Nett 64 sq.; Vism 486 sq.
-dh¤ra¼a knowledge of the Dh. M II.175;
-niy¤mat¤, certainty, or orderliness of causes and effects S II.25; Points of Controversy, 387;
-netti= niyama Miln 328; DA I.31; cp. Sk. dharmanetri M Vastu II.357; III.234, 238;
-pajjota the lamp of the Dh. Miln 21;
-pada (nt.) a line or stanza of the Dhamma, a sentence containing an ethical aphorism; a portion or piece of the Dh. . . .
-pam¤¼a measuring by the (teaching of) Dh. Pug 53; DhA III.114 . . .
-pariyatti attainment of or accomplishment in the Dh., the collection of the Dh. in general A III.86 (w. ref. to the 9 angas, see navanga);
-pariy¤ya a short discourse, or a verse, or a poem, with a moral or a text; usually an exposition of a single point of doctrine D I.46; II.93; III.116; M I.445; Vin I.40 (a single verse); A I.65; IV.63 (a poem Sn 190-218, where also it is called a dh-*pariyayo); A V.288, 291. Such a dh-*pariyaya had very often a special name. . . .
-p¤la guardian of the Law or the Dh. J V.222, freq. also as Np.;
-p¨ti (-rasa) the sweetness of drinking in the Dh. (piva¸) Sn 257; Dh 79 . . .
-bh¤ta having become the Dh.; righteousness incorporated, said of the Buddhas D III.84. Usually in phrase (Bhagava) cakkhu-bh¬ta . . . dh-bh¬ta brahma-bh¬ta A V.226 sq. (cp. cakkhu); Th 1, 491; see also above, note B 1 a;
-bheri the drum of the Dh. Miln 21;
-magga the path of righteousness Sn 696; Miln 21;
-maya made (built) of the Dh. (p¤s¤da) S I.137;
-y¤na the vehicle of the Law (the eightfold Noble Path) S V.5;
-rakkhita rightly guarded Sn 288;
-rata fond of the Law Sn 327; Dh 364; DhA IV.95; cp. dh.-[gata]rati Th I.742; Dhp. 354;
-rasa taste of Dhp. 354;
-r¤j¤ king of righteousness, Ep. of the Buddha S I.33=55; D I.88 (of a cakkavatti); A I.109; III.149; Sn 554; J I.262; . . . a king who gained the throne legitimately;
-laddha one who has acquired the Dh., holy, pious S II.21; J III.472; justly acquired (bhoga) Sn p. 87;
-vara the best of truths or the most excellent Doctrine Sn 233, 234;
-v¤din speaking properly, speaking the truth or according to the Doctrine Vin II.285; III.175 (+Vinaya-v¤din); D III.135 (id.); D I.4, 95 . . .
-vicaya investigation of doctrine, religious research Dhs 16, 20, 90, 309, 333, 555; Vbh 106; Vism 132;
-vitakka righteous thought A I.254;
-vid¬ one who understands the Dh., an expert in the Dh. J V.222; VI.261;
-vinicchaya righteous decision, discrimination of the truth Sn 327; Dh 144; DhA III.86;
-vih¤rin living according to the Dh. A III.86 sq.;
-sa¸vibh¤ga sharing out or distribution of the Dh., i. e. spiritual gifts It 98 (opp. ¤misa* material gifts);
-sang¤haka a compiler of the sacred scriptures, a diaskeuasth/s VvA 3, 169;
-sa¾¾¤ righteous thought, faith, piety PvA 3;
-sabh¤ a hall for the discussion of the Dh., a chapel, meetinghouse J VI.333; DhA I.31; II.51; IV.91; PvA 38, 196;
-samaya a meeting where the Dh. is preached S I.26;
-sam¤d¤na acquisition of the Dh., which is fourfold as discussed at M I.305; D III.229;
-sara¼a relying on or putting one's faith in the Dh. (see above C 3) D III.58, 77; S V.154;
-savana hearing the preaching of the Dh., "going to church" Vin I.101; M II.175; A II.248, 381; IV.361; Sn 265; DhA III.190;
-s¤kaccha conversation about the Dh. Sn 266;
-ss¤mi Lord of the Truth, Ep. of the Buddha (see above B 1 a note) S IV.94;
-s¤ra the essence of the Dh. S V.402;
-s¤rin a follower of the Dh. S I.170;
-sudhammat¤ excellency of the Dh. S II.199; Th 1, 24, 220, 270, 286;
-senap¤ti "captain of the Dhamma," Ep. of Sariputta Th 1, 1083; J I.408; Miln 343; DhA III.305; VvA 64, 65, 158;
-sota the ear of the Dh. S II.43.

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