Left hand radical, side-form of
手 — the indexing radical. Marks
摔 as a forceful manual action: slamming, hurling, dropping. Even when
摔 means 'to fall down' (
摔倒), the verb keeps a sense of impact — you don't just sink, you smack the ground. Same family:
扔 throw,
推 push,
拍 slap.