clasp lock

Webster's Dictionary (GCIDE)

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. [1913 Webster]

2.A close embrace; a throwing of the arms around; a grasping, as with the hand. [1913 Webster]

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. [1913 Webster]