opening: (chapter, etc.) un-esma; komenc-anta.
opening: (act of o.) apert-o; (aperture) apert-uro (cf. brecho; fend-uro; truo); (commencement) komenco; (first appearance) debuto; (opportunity) okaziono; chanco; (for sale of goods) debit-eyo.
openly: aperte, ne-cel-ate, sincere, honeste, kandide.
opera: oper-o; o. house: -teatro; o. glass: bi-lorn-eto.
operate: (surg., finan., milit.) operacar; (work) (intr.) agar, efikar, funcionar, (in stock markets) spekular.
operation: (math., surg., milit., fin.) operaco; (in gen.) ago, efiko, funcion-ado, procedo.
operative: (n.) mestier-isto, laboristo, fabrik-anto, -isto; (adj.) ag-iva, (efficacious) efik-anta, -iva, -ema.
operculum: operkulo.
operetta: oper-eto.
ophicleide: ofikleido.
ophite: ofito.
opthalmia: oftalmio; -mic: okul-ala.
opthalmology: oftalmologio.
opthalmoscope: oftalmoskopo.
opiate: opiato, narkot-ig-ivo.
opine: (intr.) opinionar, expresar (sua) opiniono.
opinion: opiniono; to be of the o.: -ar, havar ta opiniono; to have high o. of: bone o favore opinionar pri (ulu, ulo); in the o. of: segun la opiniono di.
opinionated: obstin-anta, -ema.
opium: opiumo.
opodeldoc: opodeldoko.
opossum: sarigo.
opponent: antagonisto, adverso; opozanto, -ero (collect.) -ant-aro.
opportune: oportuna; -ness: -eso.
opportunism: oportun-ismo.
opportunist: oportun-isto, -ista.
opportunity: (occasion) okaziono, (favo(u)rable circumstance) oportun-ajo; (chance, luck) chanco; take, seize the o.: prenar, kaptar la okaziono; o. makes the thief: lokaziono facas la furt-anto, od, lokaziono sugestas krimino.
oppose: (put in opposition) opozar (ulu ad ulu, ulo ad ulo); (to resist) rezistar, kombatar; opposed to: (prep.) kontre; (verbal form) opoz-ata, -ita (ad).
opposite: opoz-ita; -ly: -ite; (cf. trans).
opposition: (contrast) opoz-eso; (act of placing opposite) opoz-o; (resistance) rezist-(ad)o, -emeso, -ivo; (opponents collect.) opozant-aro; (cf. obstaklo; konkurenco; repugn-eso).
oppress: opresar; -ion: -(ad)o; (state) -eso; -ive: -anta, -iva, -ema; -or: -anto, -ero.
opprobrious: infam-ig-anta; insult-anta, -ema, -oza; ofens-anta, -ema.
opprobrium: des-honoro, infam-eso.
oppugn: atakar.
optative (mood): optativo.
optic: (eye) okulo; -aclass="underline" relative to the eye) okul-ala; (relative to vision) vid-ala; (relative to optics) optik-ala; -ian: optik-isto (cf. okul-isto; eye-doctor).
optics: (science of) optiko.
optimism: optim-ismo.
optimist: optim-isto; -ic: -ista.
option: selekto; -aclass="underline" fakultiva, selekt-ebla. permis-ata.
opulence: rich-eg-eso, lux-ego.
opulent: rich-ega, lux-ego.
opuscule: verk-eto, libr-eto.
or: o(d); either…or: o(d)…o(d).
oracle: oraklo.
oracular: orakl-atra.
oral: parol-a, -ala; o. examination: parol-ala exameno.
orange: oranj-o (colour) -ea, -eo; o. tree: -iero; o. orchard: -ier-eyo; o. peeclass="underline" -shelo; -ade: -drink-ajo.
orang-outang: orangutano.
oration: diskurso (eloquenta); to deliver an o.: diskursar (eloquente) (pri).
orator: oratoro, diskurs-anto, -ero, -isto; parol-anto, -ero, -isto; -icaclass="underline" orator-ala, diskurs-ala.
oratorio: oratorio.
oratory: (place of prayer) preg-eyo; (eloquence) eloquent-eso; parol-arto.
orb: globo, sfero, cirklo, orbito.
orbit: orbito.
orchard: frukto-gardeno, frukt-arbor-eyo; -ist: frukt-if-isto, -kultiv-isto.
orchestra: (place; band) orkestro.
orchestrate: instrument-izar.
orchid: orkideo.
ordain: (a priest, clergyman) ordinacar; (command) imperar; (decree) dekretar.
ordeal: prob-ego.
order: (command) imperar; (milit., naval) komandar; (goods, a dinner, etc.) komendar; (put in order) ordinar (cf. aranjar, rang-izar, dispozar, regul-izar, norm-izar).
order: (disposition) ordin-o, -eso (cf. bona stando, segun la regulo); (command) impero; komando; aranjo, -uro; dis-poz-o, -eso); (class) klaso (cf. rango); (eccl. and knighthood) ordeno (cf. ordeno (cf. ordeno-insigno); (for theatre) teatro-bilieto, admis-atesto; (goods) komendo, -ajo; (money order) mandato; postal o.: postala mandato; Holy Orders: ordi; in good o.: en bona stando; in o. that: por ke (followed by imperative); (goods) made to o.: facita segun komendo; (commandes) as you o.ed: segun vua impero; (milit.) komando; till further o.s: til plusa (od, nova) imperi, komandi, komendi; out of o.: des-ordin-ita, trubl-ita, displas-ita, des-aranj-ita, (sick) malada; o. of the day: jorn-ordino; call to o.: (ri)vokar a lordino; maintain o.: mantenar ordino; put in o.: ordinar; lower orders: inferiora klasi; in order to: (conj.) por; (cf. dekreto; preskripto).
orderly: bon-ordin-a, (person) ordin-ema; regul-oza; metod-ala, -oza.
orderly: (soldier) ordonanc-o, (officer) -oficero.
ordinal: ordin-ala; (eccl.) ritu-libro.
ordinance: (decree, law) dekreto (cf. preskripto); lego; (rite) rituo.
ordinarily: ordinare, kustume, generale.
ordinary: ordinara, kustum-ala, generala; (average) meza-grada, mez-valor-a, (tolerable) pasabla.
ordinate: ordinato.
ordination: ord-izo, ordinaco.
ordnance: kanon-aro; piece of o.: -o; o. map: (militala) teren-mapo.
ordure: exkremento.
ore: erco (cf. mineralo, metalo).
oread: oreado.
organ: (instr. and part of body) organo; (mus.) orgeno; barrel o., hand o.: turn-orgeno; o. loft: orgen-tribuno.
organdy: organdio.
organic: (relative to instruments or physiology) organ-ala; (chemical) organika.
organicism: organicismo.
organism: organismo.
organist: orgen-(ple)isto.
organization: (act) organ-izo, aranjo; (state) organiz-eso, -iz-uro; (cf. konstituciono).
organize: (furnish with organs) organ-izar; (institute) institucar; (arrange, prepare) aranjar, preparar.
organzine: organzino.
orgeat: orjato.
orgy: orgio.
orichalk, orichalcum: orikalko.
orient: oriento; esto; -aclass="underline" orient-ala, (person) -ano, -ana; -alist: -al-isto; -ate: -izar (su), ri-konocar la loko o voyo; -ation: (act) -izo, (state) -iz-eso.
orifice: apert-uro, orifico, boko, truo.
oriflamme: oriflamo.
origin: origino (cf. fonto); -aclass="underline" (adj.) -ala (cf. stranja); (person) -alo, stranj-ulo; (first of things) -al-ajo; -ality: (quality, object) -al-eso, -al-ajo; -ally: origine, komence, unesme.
originate: (tr.) naskigar; produktar; inventar; iniciar; genitar; (intr.) (de-)venar, naskar, komencar, havar origino en o de; (cf. decendar).