n. someone who is a police informer; a stoolie. (Underworld.)
Tracy turned into a whistler after her last little vacation.Who's the whistler who squealed?
whistler
noun a police car US, 1971
whistler
n. someone who is a police informer; a stoolie. (Underworld. More specialized than whistle-blower.) Britney turned into a whistler after her last little vacation.