What is a giant one-eyed creature in Greek mythology called?

In Greek mythology and later Roman mythology, the Cyclopes (singular Cyclops) are giant one-eyed creatures.

Three groups of Cyclopes can be distinguished. In Hesiod's "Theogony", the Cyclopes are the three brothers Brontes, Steropes, and Arges, who made for Zeus his weapon the thunderbolt. In Homer's "Odyssey", they are an uncivilized group of shepherds, the brethren of Polyphemus encountered by Odysseus. Cyclopes were also famous as the builders of the Cyclopean walls of Mycenae and Tiryns.

From at least the fifth-century BC onwards, Cyclopes have been associated with the island of Sicily, or the volcanic Aeolian islands just off Sicily's north coast. The fifth-century BC historian Thucydides says that the "earliest inhabitants" of Sicily were reputed to be the Cyclopes and Laestrygones (another group of man-eating giants encountered by Odysseus in Homer's Odyssey).

For the ancient Greeks the name "Cyclopes" meant "Circle-eyes" or "Round-eyes", derived from the Greek "kúklos" ("circle") and "ops" ("eye").

A possible origin for one-eyed Cyclopes was advanced by the palaeontologist Othenio Abel in 1914. Abel proposed that fossil skulls of Pleistocene dwarf elephants, commonly found in coastal caves of Italy and Greece, may have given rise to the Polyphemus story. Abel suggested that the large, central nasal cavity (for the trunk) in the skull might have been interpreted as a large single eye-socket.