A piranha is a fish with famously sharp teeth. Don't go swimming in certain South American rivers if you want to avoid piranhas!

These freshwater fish are terrifyingly described as "voraciously carnivorous," meaning they eat meat with great enthusiasm. Humans aren't often bitten by piranhas, but it does happen in some parts of South America. You also can't buy a piranha as a pet in many parts of the world—and if you do, it's best not to get two of them, since the weaker fish is often killed by the stronger one.

Definitions of piranha
  1. noun
    small voraciously carnivorous freshwater fishes of South America that attack and destroy living animals
    synonyms: caribe, pirana
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    type of:
    characid, characin, characin fish
    any freshwater fish of the family Characinidae
  2. noun
    someone who attacks in search of booty
    synonyms: marauder, predator, vulture
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    a marauder and plunderer (originally operating in the bogs between England and Scotland)
    type of:
    aggressor, assailant, assaulter, attacker
    someone who attacks
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