1 [U,C] (biology) a process in which the GENETIC material of a person, a plant or an animal changes in structure when it is passed on to children, etc., causing different physical characteristics to develop; a change of this kind:
cells affected by mutation * genetic / colour mutations
2 [U,C] a change in the form or structure of sth: (linguistics) vowel mutation * In Celtic languages such as Welsh, there is a process of mutation affecting the beginning sound of a word, according to the word which comes before it. * the mutation of ethnic politics into nationalist politics
