A jingle stick is a percussion instrument with pairs of metal discs which hit together as it is shaken. They resemble part of an instrument beginning with T. The well-known song Jingle bells used to confuse me.
Jingle is used as an adjective in jingle stick, but in jingle bells it is a verb. In fact it is the imperative form of the verb ordering the bells to jingle.
Another instrument beginning with J is the Jew’s harp. Jew here may be a corruption of jaw. It is held in the mouth and struck with a finger.
A juke box plays music, but cannot really be classed as a musical instrument. Hasn’t technology changed? Now there are i-pods and mp3-players small enough to carry around, which probably give their owner far more choice of tunes than a juke box, which takes up floor space!