An instrument played with a plectrum is a guitar (6 letters), a LYRE (4 letters) or a mandolin (8 letters). The guitar is a stringed instrument that is usually played with the fingers or a pick. The LYRE is an ancient stringed instrument that was popular in Ancient Greece and is still used in some cultures today. The mandolin is a stringed instrument that is similar to a lute and is often used in folk music.