A simple membranophone instrument, now usually regarded as a toy into which the performer 'hums' or sings. It amplifies the voice, giving it a buzzing quality.

The kazoo is a type of mirliton - a device which modifies the sound of a person's voice by way of a vibrating membrane. Such instruments have been used in Africa for hundreds of years, to disguise the sound of somebody's voice or to imitate animals, often for various ceremonial purposes. It was on such an instrument that the kazoo, invented by an African American named Alabama Vest in the 19th century in Macon, Georgia, is based.

The kazoo is played professionally in jug bands and comedy music, and by amateurs everywhere. It is one of the few acoustic instruments to be developed in the USA and one of the easiest melodic instruments to play well, requiring only the ability to hum in tune.