In the Atra-hasis epic, Atrahasis is the man warned about the coming flood.
Atrahasis is the central human figure of an Old Babylonian Mesopotamian poem preserved on clay tablets. The god Enki, also called Ea, warns him about the gods' decision to send a devastating flood. Atrahasis builds a boat and survives with people, animals, and provisions.
The poem is one of the important ancient flood traditions studied alongside Genesis and the flood episode in the Epic of Gilgamesh. The Gilgamesh version uses the name Utnapishtim for its flood survivor, while Atra-hasis preserves a different form of the story and character name.
Atrahasis is therefore not Noah, Utnapishtim, or the epic hero Gilgamesh. The name can appear as “Atrahasis” or “Atra-hasis” depending on the transliteration and title of the edition. The answer here follows the common English form used for the epic's hero.