"3WW" is a song by British indie rock band alt-J. It is the opening track and first single from their third studio album, Relaxer, and was released as a digital single on 6 March 2017 by Infectious Music and Atlantic Records. The song was written by Joe Newman, Gus Unger-Hamilton, Thom Sonny Green and produced by Charlie Andrew. It features guest vocals from British musician Ellie Rowsell of Wolf Alice. The song's title is an abbreviation of "three worn words", a phrase which is sung in the song.