| orography | Orographie |
| orography of terrain | Geländeformation |
| Oroks | Oroken |
| orolabial herpes | Lippenherpes |
| Orologio | Orologio |
| orology | Orographie |
| oromandibular | oromandibulär |
| oromandibular dystonia | oromandibuläre Dystonie |
| Oromia Region | Oromiyaa |
| Oromo | Oromo |
| Oromo language | Oromo |
| Oron | Oron |
| Oron-la-Ville | Oron-la-Ville VD |
| Oron-le-Châtel | Oron-le-Châtel VD |
| Orona | Orona |
| Orontes River | Nahr al-Asi |
| oropharyngeal airway , OPA | Oropharyngealtubus |
| oropharyngeal bacterial flora | oropharyngeale Bakterienflora |
| oropharyngeal cancer | Oropharynxkarzinom |
| oropharyngeal candidiasis , OC | Candidiasis der Mundhöhle und des Rachens |
| oropharyngeal carcinoma | Oropharyngealkarzinom |
| Oropos | Oropos |
| Oropouche fever | Oropouche-Fieber |
| Oropouche virus | Oropouche-Virus |
| Oropouche viruses | Oropouche-Viren |
| Oroqen | Oroqen |
| Oroquieta City | Oroquieta City |
| Orosirian | Orosirium |
| Orosius | Orosius |
| orotate | Orotat |
| Orotic acid | Orotsäure |
| orotic aciduria | Orotazidurie |
| orotracheal anaesthesia | orotracheale Narkose |
| orotracheal intubation | orotracheale Intubation |
| orotund | bombastisch |
| orotund voice | volle Stimme |
| orotundity | Schwulst |
| Oroville | Oroville |
| Oroya fever | Oroya-Fieber |
| ORP Błyskawica | ORP Błyskawica |
| ORP Grom | ORP Grom |
| ORP Orzeł | ORP Orzeł |
| ORP Żbik | ORP Żbik |
| orphan | Findelkind |
| orphan boy | Waisenknabe |
| orphan boys | Waisenjungen |
| orphan child | Waisenkind |
| orphan children | Waisenkinder |
| orphan disease | seltene Erkrankung |
| Orphan drug | Orphan-Arzneimittel |
| orphan drugs | Arzneimittel für seltene Leiden |
| orphan girl | Waisenmädchen |
| orphan girls | Waisenmädchen |
| orphan line | Schusterjunge |
| Orphan of Creation | Waisen der Schöpfung |
| orphan receptor | Waisen-Rezeptor |
| Orphan works | Verwaistes Werk |
| orphan's court | Nachlassgericht |
| orphan's social benefit | Waisenrente |
| orphanage | Waisenhaus |
| orphaned | verwaist |
| orphaned puppies | verwaiste Welpen |
| orphanhood | Waisentum |
| orphanry | Waisenhaus |
| orphans | Waisenkinder |
| Orphans of the Sky | Universum |
| Orphans of the Storm | Zwei Waisen im Sturm |
| orphans' pension | Waisengeld |
| Orpharion | Orpheoreon |
| Orphean Warbler | Orpheusgrasmücke |
| Orpheus | Orpheus |
| Orpheus in the Underworld | Orpheus in der Unterwelt |
| Orpheus With Clay Feet | Orpheus mit Pferdefuss |
| Orphic | Geheimnissvoll |
| Orphism | Orphiker |
| orphite | Orphit |
| orpiment | Auripigment |
| orpiment yellow | Auripigment |
| Orpington | Orpington |
| Orpund | Orpund |
| orreries | Planetenmodelle |
| orrery | Planetenmodell |
| orris | Florentiner Schwertlilie |
| orris oil | Irisöl |
| orris root oil | Iriswurzelöl |
| Orrorin tugenensis | Orrorin tugenensis |
| orrugated cardboard factory | Wellpappenfabrik |
| Orsa Municipality | Orsa |
| Orsanmichele | Orsanmichele |
| Orsay | Orsay |
| Orseis | Orseis |
| Orselina | Orselina TI |
| Orsha | Orscha |
| Orsingen-Nenzingen | Orsingen-Nenzingen |
| Orsini | Orsini |
| Orsini family | Orsini |
| Orsinian Tales | Geschichten aus Orsinien. Science Fiction Erzählungen aus einem erfundenen Land |
| Orsières | Orsières VS |
| Orsk | Orsk |
| Orso Ipato | Orso Ipato |
| Orson Scott Card | Orson Scott Card |
| Orson Welles | Orson Welles |
| Ort | Ort |
