Found:
Lenition
PHONOLOGY: a process of weakening. The diachronic development in (i) can be analyzed as a case of lenition (Hooper (1976), Katamba (1989)):
(i) Latin Italian Spanish French
vita vita vida vie 'life'
t -> t -> d -> 0
Lenition can be explained by referring to the
sonority hierarchy: the progression down the sonority hierarchy is from a voiceless stop to a voiced stop before deletion takes place. Lenition can also occur in one language.
| LIT. | Hooper, J. (1976) Katamba, F. (1989) |