In military slang, "Zero Dark Thirty" refers to an unspecified time in the early morning hours, typically between midnight and dawn.
The title of the 2012 film serves as both a literal reference to a specific military time and a metaphor for the secrecy surrounding the hunt for Osama bin Laden. Military Definition and Origins subtitle Zero Dark Thirty
The title replaced the initial working title, Kill Bin Laden . It was chosen for its thematic depth: In military slang, "Zero Dark Thirty" refers to
: The term is a play on the 24-hour military clock. "Zero" refers to the hours before 10 a.m. (starting with 0), "Dark" denotes the nighttime or pre-dawn hours, and "Thirty" indicates 30 minutes past the hour. In military slang
