Sir Gawain and the Green KnightSir Ga‧wain and the Green Knight /sə ˌɡɑːweɪn ənd ðə ˌɡriːn ˈnaɪt $ sər-/a long English poem written in the 14th century by an unknown poet. It is about Gawain, a brave knight in the time of King arthur, and his adventures with a mysterious green knight. →Arthurian Legend