剃刀
かみそり · kamisori · JLPT N2 · noun
razor
🪒 剃刀 = shave (剃) + blade (刀): the blade you use to shave
剃 means shave and 刀 means blade or knife. Joined, they name the tool whose blade is used for shaving hair. The reading かみそり is a separate native word, so the kanji's meaning is the best hook.
剃 — knife radical 刂 + younger brother 弟 (phonetic)
剃 is a semantic-phonetic compound: the knife radical 刂 supplies the meaning 'to cut/shave', while 弟 (dì) provides the sound, shifted to tì. Originally written 鬀 with 髟 (long hair) over 弟, it specifically meant shaving hair, especially the head.
刀 — single-component pictograph 刀 (knife/blade)
刀 is a pictograph of a single-edged knife or blade, with the curved stroke depicting the back of the blade and the hook representing the handle. Ancient bronze and oracle-bone forms clearly show a side view of a knife. It still means 'knife' today and serves as a radical in many cutting-related characters.