Utnapishtim is the ancient Mesopotamian flood hero called by that name in the Epic of Gilgamesh. In the epic’s flood story, the god Ea warns Utnapishtim to build a large boat, preserve living creatures, and survive a catastrophic flood. Afterward, Utnapishtim receives immortality.
The episode is one of the important ancient flood traditions compared with the story of Noah’s Ark. Utnapishtim’s account appears on Tablet XI of the Standard Babylonian version of the Epic of Gilgamesh. The related Atrahasis tradition also contains a flood hero, but Atrahasis is a different name in a different Mesopotamian literary work.
Gilgamesh himself is the king and central hero who seeks Utnapishtim to learn about immortality; he is not the flood survivor. Enkidu is Gilgamesh’s companion. These names are therefore plausible distractors, but the flood hero’s canonical name in this epic is Utnapishtim.