A clumsy or awkward person.

an awkward stupid person

Originally, an elf's child; a changeling left by fairies or goblins; hence, a deformed or foolish child; a simpleton; an idiot.

See origin address field (OAF).

origin address field. In SNA, a field in a format identification 0 (or format identification 1) transmission header that contains the network address of the originating location. In a format identification 2 heading, the field is called origin address field prime (OAF'). Contrast with destination address field (DAF).

Oro antral fistula. A dental term meaning a communication between the mouth and the maxillary sinus.