mu·tant (myo?ot?nt)n.1. An organism, cell, virus, or gene resulting from genetic mutation.2. Slang One that is suggestive of a genetic mutant, as in bizarre appearance or inaptitude.adj.1. Resulting from genetic mutation: a mutant strain of bacteria.2. Slang Suggestive of a genetic mutant.[Latin m?t?ns, m?tant-, present participle of m?t?re, to change; see mutate.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.mutant (?mju?t?nt) n (Genetics) Also called: mutation an animal, organism, or gene that has undergone mutationadjof, relating to, undergoing, or resulting from change or mutation[C20: from Latin mut?re to change]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014mu?tant (?myut nt) n. 1. a new type of organism produced as the result of mutation. adj. 2. undergoing or resulting from mutation. [1900?05;