The word "紧箍咒" is formed by sequentially combining three characters: 紧, meaning "tight" or "to tighten"; 箍, meaning "hoop" or "band"; and 咒, meaning "spell" or "incantation". Together, they construct a compound noun where 紧 modifies 箍 to specify a "tightening hoop", and 咒 denotes the magical aspect, resulting in a literal meaning of "tightening hoop spell", which directly describes a spell that causes a hoop to constrict.