[uh-kawr-dee-uh
n] 
| 1. | Also called piano accordion. a portable wind instrument having a large bellows for forcing air through small metal reeds, a keyboard for the right hand, and buttons for sounding single bass notes or chords for the left hand. |
| 2. | a similar instrument having single-note buttons instead of a keyboard. |
| 3. | having a fold or folds like the bellows of an accordion: accordion roof; accordion panel. |
| 4. | (of a door, roof, or other covering) to open by folding back or pressing together in the manner of an accordion: The roof of the car accordions to let in sunlight and fresh air. |
| 5. | to fold, crush together, or collapse in the manner of an accordion. |
| 6. | to demolish by crushing together lengthwise: The impact accordioned the car beneath the truck. |