n. In classical mythology, one of a divine but monstrous race, children of Uranus (Heaven) and Gæa (Earth), and personifying destructive physical phenomena, as those of volcanic origin.n. Some other imaginary being of human form but superhuman size: as, Giant Despair, in Bunyan's “Pilgrim's Progress.”n. Figuratively, a person of unusual size or of extraordinary powers, physical or mental.Gigantic; of extraordinary size or force, actual or relative: as, “the giant world,” ; a giant intellect.n. In gold-mining, a large nozle used to direct the powerful streams employed in hydraulic work. See cut under hydraulic.