noun
mandolin
man-duh-LIN/ˌmændəˈlɪn/
A small stringed instrument with a rounded body and paired strings.
The small mandolin has a pear-shaped body and paired strings.

Etymology
The Italian formation means a little mandola, naming the instrument as a smaller relative of a larger stringed instrument. Its diminutive ending directly reflects the size distinction.
In context
he picked up the mandolin by default and and learned how to play it on his own
More examples
- He tunes each pair of strings on his mandolin.
- The bluegrass band includes a fiddle, a banjo, and two mandolins.
- I keep my mandolin in a padded case.
Forms
mandolin · mandolins
mandolinist noun — A musician who plays the mandolin.