0 used to connect different possibilities: --
He was just kidding - or was he (= but it is possible that he was not)?
There were ten or twelve (= approximately that number of) people in the room.
It doesn't matter whether you win or lose - it's taking part that's important.
The patent was granted in (either) 1962 or 1963 - I can't quite remember which.
Are you listening to me or not?
1 if not: --
2 used to show that a word or phrase means the same as, or explains, limits, or corrects, another word or phrase: --
Things have been going very well recently. Or they were, until two days ago.
Rosalind, or Roz to her friends, took the initiative.
3 used to describe something on a coat of arms (= a special shield or shield-shaped pattern that is the sign of a family, university, or city) that is gold or yellow: --
The city's crest is a fleur-de-lys or between two roses argent.
4 abbreviation for operating room US --
5 written abbreviation for the US state of Oregon: used in addresses --
Richard III used either a lion Or and a boar argent, or two boars argent.
Football, or soccer as it's sometimes called, is very popular in the country.
Come on, stir yourselves, or you'll be late!
Are you comfortable or shall I turn the heat down?