Related Clues:

• Lab animal
• Betrayer
• Pot-bellied critter
• Porker
• Petunia, e.g.
• Blow the whistle (on)
• Ben, in a film
• Name names
• Overeat (with "out")
• Be a snitch
• Ratfink
• Eat greedily
• Lab critter
• Mob pariah
• Double-crosser