Definitions of giant:

noun: any creature of exceptional size
noun: an unusually large enterprise
Example: "Walton built a retail giant"
noun: an imaginary figure of superhuman size and strength; appears in folklore and fair tales
noun: someone or something that is abnormally large and powerful
noun: a very large person; impressive in size or qualities
noun: a very bright star of large diameter and low density (relative to the Sun)
noun: a person of exceptional importance and reputation
adjective: of great mass; huge and bulky