squealer

noun5

1. •
   Any animal or person who squeals.
2. •
   A pig.
3. •
   Anything that makes a squealing noise.
4. •
   (slang) An informant.
5. •
   (US, informal) A kind of jug used to carry beer having 1 litre or 32 ounce capacity (half the size of a growler).