Accordion n. : A small, portable, keyed wind instrument, whose tones are generated by play of the wind upon free metallic reeds.

Example:
How can you learn Accordion by yourself?

Taxonomy
accordion, instrument, bellows, reeds, bass, chords, piano accordion, musical instruments, accordionist, ranks, switches, button accordions, Chromatic button accordion, classical music, popular music, pallet, mechanism, Stradella bass.

Defination from the web:
accordion is a portable box-shaped musical instrument of the hand-held bellows-driven free-reed aerophone family, sometimes referred to as a squeezebox. ... Additionally, the accordion is sometimes used in both solo and orchestra performances of classical music. ...