IPA: /ˌpriːˈkliːnɪŋ/
KK: /priˈklēniŋ/
The act of cleaning something before another cleaning or process takes place.
Precleaning the surfaces helps ensure a more thorough cleaning later.
Precleaning → It is formed from "pre-" (meaning before) and "cleaning" (from Old English "clæne", meaning free from dirt). The word "precleaning" refers to the act of cleaning something before it undergoes further processes or cleaning steps.
Think of doing something 'before' ('pre-') the actual 'cleaning' — that's why precleaning means cleaning beforehand.