(anatomy) Synonym of bone.

(anatomy) An opening or entrance to a passage, particularly one at either end of the cervix, internal (to the uterus) or external (to the vagina).

An osar or esker.

(rare) Alternative form of o's.

(sports) Abbreviation of Owen Sound.

Abbreviation of outsize (clothes for large people) / Abbreviation of oversize.

(UK) an Ordnance Survey map. / (software) Initialism of operating system. / Abbreviation of ordinary seaman.

Used to form plurals of some Hebrew and Yiddish loanwords, usually ending in -a or -ah.

plural of O

(pharmacology) a monoclonal antibody that targets bone