Lenition is a kind of
consonant mutation that appears in many
languages. Along with
assimilation, it is one of the primary sources of
historical change of languages.
Lenition means 'softening' or 'weakening' (from Latin lenis = weak), and it refers to the change of a consonant considered 'stronger' into one considered 'weaker' (or fortis ? lenis). Common examples include voicing or sonorization, as in [f] ? [v]; affrication or spirantization (turning into an affricate or a fricative), as in [t] ? [ts] ? [s]; debuccalization (loss of place), as in [s] ? [h]; degemination, as in [k?] ? [k]; deglottalization, such as [k’] ? [k], etc. These may occur one after the other in the history of a language. Eventually, consonants may be lost completely, which is the ultimate lenition. Lenition, then, can be seen as a movement on the sonority scale from less to more sonorous.
Note This page or section contains IPA phonetic symbols in Unicode. See HelpIPA for a pronunciation key.
Two common lenition pathways are the "opening" type, where the articulation becomes more open with each step,
