The Pali Text Society's Pali-English Dictionary

Opama at J i.89 & Sdhp 93 (anopama) stands for (pama, which metri caus! for upama.
Opamma
Opamma (nt.) [fr. upama; cp. Sk. aupamya] likeness, simile, comparison, metaphor M i.378; Vin v.164;
Miln 1, 70, 330; Vism 117, 622; ThA 290.
Oparajja
Oparajja viceroyalty is v. l. for uparajja. Thus at M ii. 76; A iii.154.
Opavayha
Opavayha (adj. n.) [fr. upavayha, grd. of upavahati] fit for riding, suitable as conveyance, state -- elephant
(of the elephant of the king) S v.351 = Nett 136 (v. l. opaguyha; C. explns. by !rohana -- yogga); J ii.20 (SS
opavuyha); iv. 91 (v. l. ˚guyha); vi.488 (T. opavuyha, v. l. opaguyha; gajuttama opavayha = r!ja -- v!hana
C.); DA i.147 (!rohanayogga opavuyha, v. l. ˚guyha); VvA 316 (T. opaguyha to be corrected to ˚vayha).
Opasamika
Opasamika (adj.) [fr. upa + sama + ika; cp. BSk. aupa$amika Av. - ii.107; M Vastu ii.41] leading to quiet,
allaying, quieting; Ep. of Dhamma D iii.264 sq.; A ii.132.
Opas!yika
Opas!yika (adj.) [fr. upasaya, upa + $"] being near at hand or at one's bidding (?) M i.328.
Op!&eti
Op!&eti [ava + Caus. of pa&, Sk. avap!&ayati] to tear as- under, unravel, open Vin ii.150 (chavi' op!&etv!).
Op!ta
Op!ta [o + p!ta fr. patati to fall, Vedic avap!ta] -- 1. falling or flying down, downfall, descent J vi.561. -- 2.
a pitfall J i.143; DhA iv.211.
Op!teti
Op!teti [o + Caus. of pat] to make fall, to destroy (cp. atip!teti), i. e. 1. to break, to interrupt, in katha'
op!teti to interrupt a conversation M ii.10, 122, 168; A iii.137, 392 sq.; Sn p. 107. -- 2. to drop, to omit (a
syllable) Vin iv.15.
Op!na
Op!na (nt.) [o + p!na fr. pivati. Vedic avap!na. The P. Commentators however take o as a contracted form
of udaka, e. g. Bdhgh. at DA i.298 = udap!na]. Only in phrase op!na -- bh(ta (adj.) a man who has become
a welling spring as it were, for the satisfaction of all men's wants; expld. as "khata -- pokkhara*" viya
hutv!" DA i. 298 = J v.174. -- Vin i.236; D i.137; M i.379; A iv. 185; Vv 654; Pv iv.160; J iii.142; iv.34;
v.172; Vbh 247; Miln 411; Vism 18; VvA 286; DA 1177, 298.
Op!rambha