A female who normally would never be considered a suitable partner due to her general appearance or demeanour, but at the end of a night of unsucessful lady-hunting, suddenly becomes more appealing as a last resort at 3am.
"Did you see the ugly girl Dave went home with on saturday night?"
"Urgh yes, total 3 o'clock Princess"

"Those girls are hot, lets go over and talk to them"
"No way, that girls hot, but her friend's a 3 o'clock Princess, it's too early in the night to take that grenade.
by GaGaOhLaLa March 26, 2010
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