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hundred-eyed giant of Greek mythology, late 14c., from Latin, from Greek Argos, literally "the bright one," from argos "shining, bright" (see argent). His epithet was Panoptes "all-eyes." After his death, Hera transferred his eyes to the peacock's tail. Used in figurative sense of "very vigilant person."
A creature in classical mythology who had a hundred eyes. Hera set him to watch over Io, a girl who had been seduced by Zeus and then turned into a cow; with Argus on guard, Zeus could not come to rescue Io, for only some of Argus' eyes would be closed in sleep at any one time. Hermes, working on Zeus' behalf, played music that put all the eyes to sleep and then killed Argus. Hera put his eyes in the tail of the peacock.
figure in Greek legend described variously as the son of Inachus, Agenor, or Arestor or as an aboriginal hero (autochthon). His byname derives from the hundred eyes in his head or all over his body, as he is often depicted on Athenian red-figure pottery from the late 6th century BC. Argus was appointed by the goddess Hera to watch the cow into which Io (Hera's priestess) had been transformed, but he was slain by Hermes, who is called Argeiphontes, "Slayer of Argus," in the Homeric poems. Argus's eyes were transferred by Hera to the tail of the peacock. His fate is mentioned in a number of Greek tragedies from the 5th century BC-including two by Aeschylus, Suppliants and Prometheus Bound, and Euripides' Phoenician Women-and the Latin poet Ovid's Metamorphoses from the 1st century AD