thirty(redirected from thirties)
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oh dark thirty
In military time, a non-specific time in the early morning, before the sun rises. Why on earth are we meeting at oh dark thirty? That's too early to do anything besides sleep!
1. adjective Of an unspecified age in one's thirties. He looks like he's in his 50s, but he's really just thirty-something.
2. noun A person who is in their thirties. Usually used in the plural. With so many college students in this town, it's nice to find a place that's geared more for thirty-somethings.