noun a dunce; a stupid fellow.
2. booby ·noun a species of penguin of the antarctic seas.
3. booby ·adj having the characteristics of a booby; stupid.
4. booby ·noun a swimming bird (sula fiber or s. sula) related to the common gannet, and found in the west indies, nesting on the bare rocks. it is so called on account of its apparent stupidity. the name is also sometimes applied to other species of gannets; as, s. piscator, the red-footed booby.