Clasp \Clasp\, n. 1. An adjustable catch, bent plate, or hook, for holding together two objects or the parts of anything, as the ends of a belt, the covers of a book, etc. 2. A close embrace; a throwing of the arms around; a grasping, as with the hand. {Clasp knife}, a large knife, the blade of which folds or shuts into the handle. {Clasp lock}, a lock which closes or secures itself by means of a spring.