In Greek mythology, Thaumas (also Thaumant) was a sea-god, one of the children of Pontus (Sea) and Gaia (Earth), and thus the full brother of Nereus, Phorcys, Ceto, and Eurybia. By the Oceanid Electra he was the father of Iris, the divine messenger, and of the storm-winds known as the Harpies. His name was connected by Plato with the Greek word for "wonder."
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I.Etymology
Plato associated Thaumas's name with the Greek word θαῦμα (thauma), meaning "wonder." The connection suits a sea-god whose daughter is Iris, the rainbow and divine messenger.
II.Family
Thaumas was a sea-god, born of the union of Pontus (Sea) and Gaia (Earth). He was therefore counted among the primeval children of the deep, the full brother of Nereus, Phorcys, Ceto, and Eurybia.
He married Electra, an Oceanid, the daughter of the Titans Oceanus and Tethys. Through her he became the father of a notable line of divine offspring.
III.Mythology
According to Hesiod, the children of Thaumas and Electra included Iris, the divine messenger goddess; Arke, who had formerly served as the messenger of the Titans; and the Harpies.
Ancient sources name the Harpy daughters variously. Hesiod and Apollodorus call them Aello and Ocypete; Virgil names Celaeno; and Hyginus gives conflicting lists across his works, citing Celaeno, Ocypete, and Podarce in one place and Aellopous, Celaeno, and Ocypete in another.
The 5th-century poet Nonnus described Thaumas and Electra as the parents of just two children: Iris and the river-god Hydaspes.
IV.Other figures of the name
A centaur named Thaumas also appears in Greek myth, fighting against the Lapiths during the Centauromachy. This Thaumas is an entirely separate mythological figure and should not be confused with the sea-god.