Enter a clue or pattern or both:
The ClueRat fink (7 letter answer)
NotesThe answer STOOLIE is seen occasionally, appearing about once every 900 puzzles.
One who sings
He rats to the cops
One who sings but maybe shouldn't
DefinitionSTOOLIE as a noun:
1. (fink, snitch, snitcher, stoolpigeon, stool pigeon, stoolie, sneak, sneaker, canary) = someone acting as an informer or decoy for the police