Sung out is a phrase used to describe the act of singing until your voice becomes tired or hoarse. The antonyms for this phrase include quiet, silent, hushed, or muted. These words describe a situation where there is no singing or sound being made. Other antonyms for the phrase "sung out" may include calm, still, tranquil, and peaceful. These words refer to a state of relaxation or serenity, where one's voice is not being exerted. Overall, the antonyms for "sung out" describe the opposite of the act of singing, whether it be through silence or a state of calmness.