The Claypool Lennon Delirium is an American psychedelic rock band, currently composed of bassist/vocalist Les Claypool, known for his work on Primus, and guitarist/vocalist Sean Lennon.
Originally conceived in 2015, with Claypool knowing that Primus would take a year off after touring alongside The Ghost Of A Saber Tooth Tiger and Dinosaur Jr.. He kept in touch with The Ghost Of A Saber Tooth Tiger's lead singer Sean Lennon, who had not planned any musical project for the following year.