a musical instrument that usually has six strings, that you play with your fingers or with a plectrum an acoustic/an electric/a classical, etc. guitar a guitar player Do you play the guitar? She plays guitar in a band. As he sang, he strummed his guitar. He gently plucked his guitar. He would stand in front of the mirror, playing air guitar to Van Halen songs. see also air guitar, bass1 See related entries: Musical instruments Word Origin early 17th cent.: from Spanish guitarra (partly via French), from Greek kithara, denoting an instrument similar to the lyre.