A kollops (Greek: κολλοψ or kollabos) is a tuning device for a string instrument (generally a lyre) which consists of a strip of leather wrapped around the instrument's crossbar, tightened by a wooden peg trapped in its wrap. The device is mentioned as early as the 7th century BC, used metaphorically in the Odyssey. The material itself, usually the hard materia the back of the neck of an ox, was known as "kollops", and thus the term was also used for the tuning device.