means A hook is a curved or bent piece of metal, wood, or other material used to catch, hold, or hang something — and by extension, anything that catches and holds attention, like the catchy part of a song.

from From Old English 'hoc,' a curved tool for catching, with relatives across the Germanic family — Dutch 'hoek' and German 'Haken' among them — all tracing back to a root meaning 'to bend.' The thing was literally a bent shape, and the word never lost that curve: a fishhook bends to snag a fish, a boxer's hook bends the arm, and a musical hook bends your ear back for one more listen.