空手 (kōng shǒu) literally means 'empty hand' — 空 (kōng) means 'empty' or 'vacant', and 手 (shǒu) means 'hand'. As an adjective, it describes a person carrying nothing — especially no tools, weapons, gifts, or belongings. As an adverb, it modifies verbs like 来 (come), 去 (go), or 回 (return), indicating the action was done without anything in hand.

The term is commonly used in everyday situations: arriving at a friend’s home without a gift ('came empty-handed'), leaving a store without buying anything, or practicing martial arts without weapons (e.g., 空手道 kōngshǒudào, 'karate'). It carries neutral to slightly apologetic connotations — saying 空手而来 often implies modesty or regret for not bringing something appropriate.