Definition of "OR"
OR
noun
countable and uncountable, plural ORs
(healthcare, countable) Initialism of operating room.
(sciences, uncountable) Initialism of operations research.
(sports, countable) Initialism of Olympic Record.
(anatomy, countable) Initialism of odorant receptor.
(anatomy, countable) Initialism of olfactory receptor.
(Wikimedia jargon) Initialism of original research.
(military) Initialism of other ranks.