acoustic guitar

US /əˌkuː.stɪk ɡɪˈtɑːr/
UK /əˌkuː.stɪk ɡɪˈtɑːr/
"acoustic guitar" picture
1.

a guitar that produces sound by means of vibrating strings and a hollow resonating body, without electrical amplification

:
He played a beautiful melody on his acoustic guitar.
Many folk songs are best performed with an acoustic guitar.