Definition of lenition in English:

lenition

Pronunciation /ləˈniSH(ə)n/ /ləˈnɪʃ(ə)n/

noun

  • The process or result of weakened articulation of a consonant, causing the consonant to become voiced, spirantized, or lost.

    • ‘The grammar involved in medieval Gaelic names often includes lenition, a "softening" of the initial consonant sound of words or names required by Gaelic grammar in certain situations.’

Origin

Early 20th century from Latin lenis ‘soft’+ -ition, suggested by German Lenierung.