0-dark-thirty

Noun

 * 1)  Half an hour past 12(am) midnight, or more formal and exact would be 00:30; The practice of adding “dark” and “thirty” (30) can be used sometimes as a slang term in place of an otherwise specific time a time of night, meaning some time when it is dark out between 00:01 - 05:00 hours local time.

Synonyms

 * , ; see also Thesaurus:early morning