mutant

plural mutants

1. biologyThat which has mutated, with one or more new characteristics from a mutation.

   Furthermore, it is possible that there occasionally arises what may be called a mutant of very desirable character from a eugenic point of view.

   1918, Paul Popenoe, Roswell Hill Johnson, Applied Eugenics

   2 more examples

   There does seem to have been some mutation among plants[…]but in animal life where are the mutants? When or where has a new species originated in this way?

   1922, John Burroughs, The Last Harvest

   "How did I ever get such ability?" he wondered. "No one else in our family has it. Am I some sort of a mutant? But if so, how or why? I never heard Dad or Mother mention it."

   1953, E. Everett Evans, Man of Many Minds

2. informalSomeone or something that seems strange, abnormal, or bizarre.

   Your neighbor seems to be a mutant; he’s so cringy!

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   She could really get to like this relationship with Raven, if it weren't for the fact that he's a homicidal mutant.

   1992, Neal Stephenson, Snow Crash, page 364

3. computingSynonym of mutex.

   Synonyms: mutex

4. computingA changed version of a program, developed as part of mutation testing.

1. not comparablebiologyOf, relating to, undergoing (i.e. mutating), or resulting from change or mutation; that has undergone mutation.

   mutant DNA

   2 more examples

   Scientists have created a mutant enzyme that breaks down plastic drinks bottles—by accident.

   2018 April 16, Damian Carrington, “Scientists accidentally create mutant enzyme that eats plastic bottles”, in The Guardian

   Researchers at the SSI found that antibodies from people who recovered from coronavirus were less effective at neutralising the mutant strain, but have not made details of their experiments public.

   2020 November 8, Ian Sample, “UK scientists seek mutant Covid samples from Danish mink farms”, in The Guardian

2. informalnot comparableStrange, abnormal, or bizarre.

   Your mutant brother just growled at me again!

   1 more example

   Boris Johnson got an angry response after telling school pupils that the exam results crisis was caused by a “mutant algorithm” and he was glad it had been “sorted out”.

   2020 August 26, Heather Stewart, quoting Boris Johnson, “Boris Johnson blames ‘mutant algorithm’ for exams fiasco”, in The Guardian