O.s. definitions

O.S.

O.S. is Australian slang for overseas.
Found on http://www.probertencyclopaedia.com/browse/ZO.HTM

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O.S.

See oral surgery.
Found on https://www.encyclo.co.uk/local/22242

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O.S.

[Latin] Oculus sinister, left eye
Found on https://www.encyclo.co.uk/local/22446

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