noun
Refers to the act of rubbing, scrubbing, or scraping a surface, often to clean or polish it.
汚れがひどいので、擦りが必要だ。
The dirt is so bad that scrubbing is needed.
靴の泥を擦りで落とした。
I removed the mud from my shoes by scrubbing.
擦る is the verb meaning 'to rub' or 'to scrub', while 擦り is the noun form referring to the action itself.
Noun form of the verb 擦る (こする, 'to rub'). The kanji 擦 is used for rubbing or friction.