Definition from Wiktionary, the free dictionary
First attested in 1590s. Origin unknown; probably derived from the verb "to cleave". If so, the word ultimately may stem from Scandinavian: compare Old Norse kljufa (to split).
- A U-shaped coupling having holes at each end, through which a bolt is run; used especially to fit attachments to a tractor or other vehicle as it allows a degree of rotation about the bolt.