giant

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A person or thing of great size.
2. n. A person or thing of extraordinary power, significance, or importance: a giant in the field of physics; automotive industry giants.
3. n. Greek Mythology One of a race of humanlike beings of enormous strength and stature who were destroyed in battle with the Olympians.
4. n. A being in folklore or myth similar to one of these beings.
5. adj. Marked by exceptionally great size, magnitude, or power: a giant wave; a giant impact.

Century Dictionary and Cyclopedia

1. 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. They were subdued by the Olympian gods after a war which forms a favorite subject in ancient art (see gigantomachy), and typifies the inherent opposition between darkness and light.
2. n. Some other imaginary being of human form but superhuman size: as, Giant Despair, in Bunyan's “Pilgrim's Progress.”
3. n. Figuratively, a person of unusual size or of extraordinary powers, physical or mental.
4. Gigantic; of extraordinary size or force, actual or relative: as, “the giant world,” ; a giant intellect.
5. n. In gold-mining, a large nozle used to direct the powerful streams employed in hydraulic work. See cut under hydraulic.

Wiktionary

1. n. A mythical human of very great size
2. n. mythology Specifically, any of the Gigantes, the race of giants in the Greek mythology.
3. n. A very tall person.
4. n. A tall species of a particular animal or plant.
5. n. astronomy A star that is considerably more luminous than a main sequence star of the same temperature (eg. red giant, blue giant).
6. n. computing An Ethernet packet that exceeds the medium's maximum packet size of 1,518 bytes.
7. n. A very large organisation.
8. adj. very large

GNU Webster's 1913

1. n. A man of extraordinari bulk and stature.
2. n. A person of extraordinary strength or powers, bodily or intellectual.
3. n. Any animal, plant, or thing, of extraordinary size or power.
4. adj. Like a giant; extraordinary in size, strength, or power

WordNet 3.0

1. n. a very large person; impressive in size or qualities
2. n. someone or something that is abnormally large and powerful
3. n. a person of exceptional importance and reputation
4. n. an unusually large enterprise
5. adj. of great mass; huge and bulky
6. n. any creature of exceptional size
7. n. an imaginary figure of superhuman size and strength; appears in folklore and fairy tales
8. n. a very bright star of large diameter and low density (relative to the Sun)