It features Holly Nelson, who would later work regularly with bassist Eric Campuzano in the band Stranger Kings, as well as releasing a solo album on guitarist Andy Prickett & Campuzano's label Northern Records. Producer Steve Hindalong also plays harmonica on the track.
Worm was one of the last songs written before going into the studio to record Shawl. At the time of release, Campuzano said it was the best song on the record. The band described it as "a sad song about one's failure in a relationship".
The record label asked the band to change the title of the song, but Campuzano pushed back explaining “that is the feeling of the song, you feel like a worm”. The label still couldn’t understand him.
A demo of the song appears on the bootleg release The Basement Tapes.
For the 25th anniversary celebrations of the album, Leigh Nash of Sixpence None The Richer was lined-up to sing the female vocal at the Nashville show, but had to pull out.