boo·by 1 
(bbē)
(bbē)n. pl. boo·bies
1. Any of several seabirds of the genera Sula and Papasula of tropical and subtropical waters, having a pointed bill and tail, long wings, and a light-colored underside.
2. A person regarded as stupid.
[Spanish bobo, stupid, foolish, booby (because the seabirds can be caught easily when they alight on ships at sea), from Latin balbus, stammering, of imitative origin.]