Language change processes:
Conversion (grammatical change) - a word shifts from one word class to another e.g., text, favourite, friend, googling and Blairite.
Phonological change - adapting a loan word to fit a language's sound system e.g., restaurant, rendez-vous
Semantic (change in meaning) - amelioration (wicked, bad), pejoration (villain), narrowing (meat used to generally mean food, man), broadening (web, window, mouse)