Spearow is one of the original 150 Pokemon, and a decent bird pokemon. He's a bit more powerful than Pidgey, but his use diminishes as the game progresses. I never used him much.
His name is an obvious corruption of "sparrow". It's original Japanese name is オニスズメ (Onisuzume) which is derived from 鬼 (Oni) which means "demon", and 雀 (Suzume) which means "sparrow".