snitch

Short definition from Wiktionary

Verb

1. 1
   To inform on, especially in betrayal of others.
2. 2
   To contact or cooperate with the police for any reason.
3. 3
   To steal, quickly and quietly.

Noun

1. 1
   A thief.
2. 2
   An informer, one who betrays their group.
3. 3
   A nose.
4. 4
   A tiny morsel.
5. 5
   A ball used in the sport of Quidditch: the Golden Snitch.