Celtchar, son of Uthechar or Uthidir, is a character from the Ulster Cycle of Irish Mythology. In Scéla Mucce Maic Dathó he is described as "a grey, tall, very terrible hero of Ulster". When he challenges Cet mac Mágach for the champion's portion, Cet counters that he once emasculated Celtchar with a spear at Celtchar's own house. He lives in Dún Lethglaise, also known as the Mound of Down, or Rathkeltair in Downpatrick, County Down. His wife is Findmór of Dún Sobairche. He wields a spear or lance, the Lúin Cheltchair, whose lust for blood is so great it has to be dipped in a cauldron of poison to control it.