1 definition by echoseven75

Top Definition
A humorous way to declare an unknown time in the wee hours of the morning. Especially used by military personnel to describe an unwanted time to be awake or awaken. Usually pronounced "oh" dark thirty.
"What time is morning formation?"

"Have no clue, oh dark thirty I imagine!"

Sgt. Hanson always has us up at zero dark thirty for our morning runs!
by echoseven75 November 29, 2013

Mug icon
Buy a Zero dark thirty mug!