guitar

n. six or twelve-stringed musical instrument with a long fretted neck

The guitar is a musical instrument with ancient roots that is used in a wide variety of musical styles. It typically has six strings, but four, seven, eight,  ten, and twelve string guitars also exist. Guitars are recognized as one of the primary instruments in blues, country, flamenco, rock music, and many forms of pop. There is also a solo classical instrument. Guitars may be played acoustically, where the tone is produced by vibration of the strings and modulated by the hollow body, or they may rely on an amplifier that can electronically manipulate tone. Such electric guitars were introduced in the 20th century and continue to have a profound influence on popular culture.
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Noun
1. a stringed instrument usually having six strings; played by strumming or plucking
(hypernym) stringed instrument
(hyponym) acoustic guitar
(part-meronym) fingerboard

(n.)
A stringed instrument of music resembling the lute or the violin, but larger, and having six strings, three of silk covered with silver wire, and three of catgut, -- played upon with the fingers.
  

Charango - based on the European guitar and mandolin, this intrument with 10 strings has a "sound body" made from the armour of the armadillo.