OA

'OA', 'Oa', or 'oa' is an abbreviation that can stand for:

★ o/a (also o.a. or oa), an abbreviation for overall, used when describing the length of a ship.

★ Oa, a digraph

★ Oa, a fictional planet in DC Comics

★ Obavještajna agencija, the Croatian Intelligence Agency.

★ Oficina Anticorrupción, an Argentine law enforcement agency.

★ Old Alleynian, Old boy of Dulwich College.

★ Olympic Airlines, the IATA code.

★ , is abbreviated to ''o.a.'' in the Dutch language; it means ''amongst others''.

★ Open access, the free online availability of digital content.

★ Operational amplifier in electronics.

★ Order of Appearance, a less-used synonym for Order of Battle.

★ Order of the Arrow, the honor society of the Boy Scouts of America.

★ Order of Australia, an Australian formal honour.

★ ''Oriens Antiquus'', a scientific journal.

★ Original Advocacy, in the National Forensics League.

★ Orion's Arm, a collaborative, hard sci-fi world-building project.

★ Osteoarthritis, A degenerative disease of joints.

★ Overeaters Anonymous, for compulsive overeaters.