without leaving any; all of it
好き嫌いせず、残さず食べましょう。
Let’s eat everything without being picky or leaving anything behind.
朝食は残さず食えよ
Make sure you finish your breakfast.
— レベッカ (1940)
残さず飲んで食べなさい。
Finish all your food and drink.
泥棒は何の跡も残さずに逃げた。
The thief escaped without leaving a trace.
食事は残さず食え
Finish all your food.
— es［エス］ (2001)