a musical instrument with keys, metal reeds, and a bellows: it is played by alternately pulling out and pressing together the bellows to force air through the reeds, which are opened by fingering the keys
adjective
having folds, or folding, like the bellows of an accordion: accordion pleats
A portable wind instrument with a small keyboard and free metal reeds that sound when air is forced past them by pleated bellows operated by the player.
adjective
Having folds or bends like the bellows of an accordion: accordion pleats; accordion blinds.