Tara Jane O'Neil (born November 22, 1972) (surname sometimes written as "ONeil"; sometimes credited as TJO) is an American multi-instrumentalist, songwriter, audio recording engineer, and visual artist based out of Los Angeles, California, United States.

O'Neil began her music career as the bass guitarist and vocalist for the influential Louisville, Kentucky post-rock group Rodan.

Her work has been exhibited in New York City, Barcelona, Tokyo, Kyoto, Louisville, and Portland, among other places.

A Blighted Bestiary was published by Yeti Publications, including an album of live recordings, four-track demos, and outtakes.

O'Neil starred in the 1994 indie film Half-Cocked as herself, credited as "Rhonda" although her character has also been referred to as "Tara."