The didgeridoo (also spelled didgeridu, among other variants), is a wind instrument made from hollow wood, played with constantly vibrating lips to produce a continuous drone while using a special breathing technique called circular breathing. It was developed by Aboriginal peoples of northern Australia and is strongly associated with Indigenous Australian music.

A didgeridoo is usually cylindrical or conical, and can measure anywhere from 1 to 3 m (3 to 10 ft) long. Most are around 1.2 m (4 ft) long. Generally, the longer the instrument, the lower its pitch or key. However, flared instruments play a higher pitch than unflared instruments of the same length. The didgeridoo is classified as a wind instrument and is similar in form to a straight trumpet, but made of wood. It has also been called a dronepipe.

The first didgeridoos, played by aborigines an estimated 1,000-1,500 years ago (based on the dating of rock art paintings) were made from fallen eucalyptus branches that had been hollowed out by termites. Modern didgeridoos are commonly made from eucalyptus, bamboo, and agave.

In theory, any enclosed column of air, such as a PVC pipe can be made into a didgeridoo by blowing through it. Therefore, the instrument may also be made from a large variety of materials such as glass, leather, ceramic, aluminum and other metals.

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