oh dark 

(Usually military) Slang term used to describe a very early hour in the morning.

We may as well catch some sleep this afternoon, 'cause it's wheels up at oh dark thirty.

oh dark by Depleted Uranium October 21, 2008

oh dark 30 

05:30 in military time is pronounced
Oh five thirty

Oh dark thirty (o dark 30) means usually getting up at some unreasonable, unnatural, ungodly early time such as 2am when you usually get up at 6:30.

It does not really mean half passed the hour. Just a early time.

To beat the traffic for our trip, we need to get up at oh dark 30.

oh dark 30 by CarlosRicochet! October 24, 2017

oh-dark-hundred 

Period from 00:00 (zero o'clock) until 05:59 (fifty-nine past five).

Oh-dark-hundred.

oh-dark-hundred by Çpovipoviski July 18, 2025

oh-dark-hundred 

Synonym for postmidnight.

Oh-dark-hundred.

oh-dark-hundred by Çwçwçwçwçw July 31, 2025

oh-dark-thirty 

Synonym for postmidnight.

Oh-dark-thirty.

oh-dark-thirty by Ñwñwñwñwñwñw August 3, 2025

oh-dark-hundred 

Period between 00:00 (12:00 am) until 05:59 (5:59 am).

Oh-dark-hundred.

oh-dark-hundred by ÑÇWÑÇWÑÇWÑÇWÑÇWÑÇW August 7, 2025

oh-dark-thirty 

Period between 00:00 (12:00 am) until 05:59 (5:59 am).

Oh-dark-thirty.

oh-dark-thirty by ÑÇWÑÇWÑÇWÑÇWÑÇWÑÇW August 7, 2025