oh dark hundred

== English == === Alternative forms === 0-dark-hundred === Etymology === From military time, in which hours before 10:00 am are prefixed with a zero, read as "oh", and 00 minutes is read as "hundred", as in oh five-hundred for 5:00 am. === Noun === oh dark hundred (idiomatic) Some unspecified hour in the early morning (implies an unpleasant time to be awake) ==== Synonyms ==== crack of dawn, stupid o'clock, wee small hours; see also Thesaurus:early morning ==== Related terms ==== 0-dark-thirty dark thirty oh dark thirty zero dark thirty