Metathesis Definition & Meaning – Merriam-Webster

metathesis
noun
me·tath·e·sis mə-ˈta-thə-səs 
plural metatheses mə-ˈta-thə-ˌsēz 
: a change of place or condition: such as
a
: transposition of two phonemes in a word (as in the development of crud from curd or the pronunciation \ˈpər-tē\ for pretty
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