day-for-day; day to day adverb serving a prison sentence without any reduction in the sentence for good behaviour US,1990
“Let me explain something so you understand,” Stick said. “See, I did seven years straight up day to day in a room six and half feet wide by ten feet deep” — Elmore Leonard, Stick, p. 84, 1983
— Charles Shafer, FolkSpeechinTexasPrisons, p. 202, 1990