| ORIBATID | • oribatid n. (Zoology) Any of a group of mites of the suborder Oribatida. • ORIBATID n. any of a family of eyeless mites. |
| ORICHALC | • orichalc n. Alternative form of orichalcum. • ORICHALC n. a gold-coloured alloy, also ORICALCHE. |
| ORIELLED | • orielled adj. (Architecture) Furnished with an oriel. • ORIELLED adj. having an oriel, a projecting bay window supported with corbel or bracket. |
| ORIENTAL | • oriental adj. Alternative letter-case form of Oriental. • oriental n. Alternative letter-case form of Oriental. • Oriental adj. Of a pearl or other precious stone: having a superior lustre. |
| ORIENTED | • oriented adj. Having a specific orientation (positioning#Noun or direction). • oriented adj. (Often with with or in) Having had an orientation (an introduction to a topic or place). • oriented v. Simple past tense and past participle of orient. |
| ORIENTER | • orienter n. A person or thing that orients. • ORIENTER n. one who helps another to adjust to surroundings. |
| ORIFEXES | • ORIFEX n. (Shakespeare) an orifice. |
| ORIFICES | • orifices n. Plural of orifice. • ORIFICE n. an opening, esp. anatomical. |
| ORIGAMIS | • origamis n. Plural of origami. • ORIGAMI n. (Japanese) the art of paper folding. |
| ORIGANES | • ORIGANE n. (Spanish) wild marjoram, also OREGANO, ORIGAN, ORIGANUM. |
| ORIGANUM | • origanum n. Any herbaceous plant of the genus Origanum. • Origanum prop.n. A taxonomic genus within the family Lamiaceae – herbs, including oregano and marjoram. • ORIGANUM n. wild marjoram, also OREGANO, ORIGAN, ORIGANE. |
| ORIGINAL | • original adj. (Not comparable) Relating to the origin or beginning; preceding all others. • original adj. (Not comparable) First in a series of copies or versions. • original adj. (Not comparable) Newly created. |
| ORILLION | • orillion n. Alternative form of orillon. • ORILLION n. part of a fortification which shields guns. |
| ORINASAL | • orinasal adj. Alternative form of oronasal. • ORINASAL adj. of or relating to the mouth and nose, also ORONASAL. • ORINASAL n. a sound pronounced through both the mouth and nose. |