spook / spoōk/ inf. • n. 1. a ghost.2. a spy: a CIA spook.3. dated, offens. a contemptuous term for a black person.• v. [tr.] frighten; unnerve: they spooked a couple of grizzly bears. ∎ [intr.] (esp. of an animal) take fright suddenly: he'll spook if we make any noise.