stinkpot

1. Slang. A person who is despised.
2. A small musk turtle (Sternotherus odoratus) of the eastern and southern United States, usually found on the bottom of ponds and small streams.
3. Slang. A motorboat.
4. An earthenware jar containing combustibles emitting a suffocating smoke, formerly used in naval warfare. Also called stinkball.

The noun has 2 meanings:

Meaning #1: a person who is deemed to be despicable or contemptible
  Synonyms: rotter, rat, skunk, stinker, bum, puke, crumb, lowlife, scum bag, so-and-so

Meaning #2: small freshwater turtle having a strong musky odor
  Synonym: musk turtle