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mu·ta·tion  (my-tāshən)
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Tweet n. 1. The act or process of being altered or changed. 2. An alteration or change, as in nature, form, or quality. 3. Genetics a. A change in the nucleotide sequence of the genome of an organism or virus, sometimes resulting in the appearance of a new character or trait not found in the parental type. b. The process by which such a change occurs, either through an alteration in the nucleotide sequence coding for a gene or through a change in the physical arrangement of the genetic material. c. The nucleotide sequence, trait, or individual that results from such a change. 4. Linguistics a. A change affecting a sound or a class of sounds, such as back vowels or plosive consonants, through assimilation to another sound, as in the process of umlaut. b. A change affecting a sound or a class of sounds that is conditioned by morphological or syntactic factors rather than purely phonological factors, as in Irish, where certain words cause the lenition of the initial consonants of the following word. [Middle English mutacioun, from Old French mutacion, from Latin mūtātiō, mūtātiōn-, from past participle of mūtāre, to change; see MUTATE.] mu·tation·al adj. mu·tation·al·ly adv. |
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