A man made of wicker, used in some pagan rituals.
People danced around it, and set fire to it. It was burnt to offer sacrifices. The fire does not signify hatred or destruction, but the endless process of change and transformation that moves through all things.

Also, it is the name of a song by British Heavy Metal legends Iron Maiden, the first single that was released from their album Brave New World (2000). B-sides for the single were live versions of Powerslave, Man On The Edge, Killers and Futureal, all recorded on their 1999 Ed Hunter World Tour. Although in the video for this song does contain a 20' high Wicker Man which gets burned, the song itself is not about the pagan ritual, but it is mentioned in the lyrics, and the band thought it would make a good title.
They transformed their mascot Eddie into a 20' high Wicker Man for the liveshows on the Brave New World tour which is used as a backdrop during the song Iron Maiden, and a 12' high Eddie, also looking like a Wicker Man, comes walking on stage during The Evil That Men Do. For each show on that tour, The Wicker Man was the first song to be played each night.