What is the meaning of the name kaeden?

Fighter or friend. In Arabic it is "friend" or "companion". But its popularity in the West seems to come from Britain and Ireland. Apparently it started as a surname -Cadden,Caden,McCadden,McCaden - in Ireland, and from there went to Scotland where it eventually became a first name. Its Gaelic meaning would be "spirit of battle". "Mac" means "son of", so some interpretations are "son of battle/the spirit of battle/the battler" and also "little fighter". The Welsh also claim it with the same meaning of "spirit of battle", so it seems to be an all round Celtic name. Spelt "Keidan" in Yiddish or Hebrew it means "fortunate" or "happy".