Answer: booing

AnswerCrossword Clue
BOOING

Fan disapproval

BOOING

Showing dissent, in a way

BOOING

Unhappy fan's pastime

BOOING
Showing disapproval
BOOING
Verbal disapproval
BOOINGVoicing disapproval
BOOINGSound of disgust
BOOINGPrompting the hook
BOOINGVoicing one's disapproval