Foetus is a solo musical project of Australian musician JG Thirlwell. The project has had many similar names, each including the word 'Foetus'.note The "members" of the project are aliases of Thirlwell; they include Frank Want, Phillip Toss, and Clint Ruin. Thirlwell occasionally collaborates with other artists, but does not consider them to be members of Foetus.

In 1981, after the breakup of PragVEC, Thirlwell started his own solo music project under the name of 'Foetus Under Glass'. After the album Thaw, Thirlwell stopped changing the name; thereafter it remained simply 'Foetus'.

In November 1983, Foetus undertook a tour with Marc Almond, Nick Cave and Lydia Lunch in the quickly dissolved 'partnership' known as The Immaculate Consumptive. He has also appeared on albums recorded by The The, Einsturzende Neubauten, Nurse With Wound and Anne Hogan.

In October 1985, Thirlwell made the album Nail, which became the most popular Foetus album of all time.

Gash was issued in 1995, which led to acknowledgment from music journalists of Foetus's role in the development of industrial music.