Clunker

A fat fish in the freshwater bass species who reach 3 lbs + but never reach 5 lbs.
Could be a Largemouth bass, Smallmouth bass, Peacock, etc...
A good size bass but not good enough to be called a Hog or Pig.

Fishermen 1: *catches big bass*
Fishermen 1: "Woah check out the gut on that fatty!"
Fishermen 2: "Ya thats a Clunker!"
Fishermen 1: "What the fuck did you just say to me?..."