English Noun flat time (countable and uncountable, plural flat times) (law) A term of incarceration that is to be served by a prisoner without the benefit of any credits of time or earned deductions. (film, television) The time during which the camera is not rolling or when no activity is occuring on the set. Synonyms: deadtime, downtimeWikiwand - on Seamless Wikipedia browsing. On steroids.