When an animal's genes change, or mutate, the new form of the animal that results is a mutant. One example of such a mutant is a blue lobster. Another is the teenage mutant ninja turtle.

You can use the scientific term mutant for any plant or animal that's the result of a change, or mutation, in the DNA of that organism. When the word is used as an adjective, it describes something having to do with this kind of mutation, like a mutant chromosome or a mutant lobster. Mutant stems from the Latin mutantem, which means "changing."

Definitions of mutant
  1. noun
    an animal that has undergone mutation
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    type of:
    animal, animate being, beast, brute, creature, fauna
    a living organism characterized by voluntary movement
  2. noun
    (biology) an organism that has characteristics resulting from chromosomal alteration
    synonyms: mutation, sport, variation
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    freak, lusus naturae, monster, monstrosity
    a person or animal that is markedly unusual or deformed
    the largest or most massive thing of its kind
    type of:
    being, organism
    a living thing that has (or can develop) the ability to act or function independently
  3. adjective
    tending to undergo or resulting from mutation
    “a mutant gene”
Word Family

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