A will-o'-the-wisp is a pale blue atmospheric ghost light sometimes seen at night over bogs and swamps.

Will-o'-the-wisp may also refer to:

Arts and entertainment Characters Will o' the Wisp (comics), a Marvel comic book supervillain physicist Will-o'-wisp (Dungeons & Dragons), a malevolent entity in Dungeons & Dragons Will o' the wisps, fictional characters in the 2012 animated film Brave

Music "Song Of The Will-o'-the-Wisp" (Canción del fuego fatuo), from El amor brujo, a ballet composed in 1914–15 by Manuel de Falla to a libretto by Gregorio Martínez Sierra Recorded by Miles Davis on the 1960 album Sketches of Spain Transcendental Etude No. 5 (Liszt), also known as Wills o' the Wisp Irrlicht (album) (German for "Will o' the Wisp"), a 1972 album by Klaus Schulze Will O' the Wisp (album), a 1975 album by Leon Russell, and its title track Will 'O' The Wisp, a song in the 1975 album Beginnings by Steve Howe Will-O-The-Wisp, a 1997 album by Claw Boys Claw Will o' the Wisp, a song from Opeth's 2016 album Sorceress "Will O' The Wisp", from by Blackmore's Night from the 2015 album All Our Yesterdays "Will-o-the-wisp", from the Pet Shop Boys' 2020 album Hotspot

Other arts and entertainment Peggy, the Will O' the Wisp, a 1917 film Will-o'-the-Wisp (film), a 2022 Portuguese film Will O' the Wisp (novel), a 1931 novel by Pierre Drieu La Rochelle "Will o' the Wisp", a 1999 episode of children's television show So Weird Willo the Wisp, a British cartoon series originally produced in 1981 Ori and the Will of the Wisps, a 2020 video game and sequel to Ori and the Blind Forest The Will-O'-The-Wisp, a 1947 novel by Baroness Orczy

People Willie Fleming (born 1939), professional Canadian football player nicknamed "Will o' the Wisp" Jeff Hardy (born 1977), American professional wrestler who had the ring name "Willow the Whisp" Willie Pep (1922–2006), American boxer nicknamed "Will o' the Wisps"

Other uses Ignis Fatuus, a haunted ship attraction at Morey's Piers SS Will of the Wisp a Confederate blockade running steamer Will-o'-the-wisp, a variation of Spiderette solitaire game

See also Irrlicht (disambiguation), the German name for will-o'-the-wisp