摩擦
まさつ · masatsu · JLPT N2 · noun
clash
🔥 摩 = rub, 擦 = rub: two rubs make friction
Both characters mean rub or scrape, so the compound simply doubles the idea: surfaces rubbing against each other. Chafe is the skin version of the same word.
擦 — hand radical 扌 + 察 (chá, inspect)
擦 is a phono-semantic compound. The hand radical 扌 indicates the meaning — an action done with the hand, namely rubbing, wiping, or scrubbing. The right side 察 supplies the sound, giving the modern reading cā. The character is relatively late and has always centered on the idea of friction by hand.