• (n.) Too frequent use of the letter m, or of the sound represented by it.
A form of stammering in which the letter m is frequently substituted for other consonants. ... Synonym: mutacism. ... Origin: G. My, the letter u ... (05 Mar 2000) ... 
My'ta·cism noun [ Greek .... Confer Metacism .] Too frequent use of the letter m , or of the sound represented by it. 
Type: Term Pronunciation: mī′tă-sizm Definitions: 1. A form of stammering in which the letter m is frequently substituted for other consonants. Synonyms: mutacism