IPA: /ˌleɪbiəlaɪˈzeɪʃən/
KK: /ˌleɪbiəlaɪˈzeɪʃən/
A speech feature where the lips are rounded or contracted while pronouncing certain sounds, usually consonants.
In phonetics, labialization can change the way a consonant is pronounced, making it sound different from its non-labialized form.
Labialization → It is formed from "labium" (from Latin, meaning lip) and "-ization" (meaning the process of making or becoming). The word describes the process of modifying a sound to be produced with the lips, hence relating to lips.
Think of 'lips' ('labium') being involved in a process ('-ization') — that's why labialization refers to the process of producing sounds with the lips.