In Greek mythology, Nisus referred to two different people.
- One was King of Megara, and he was invincible as long as a lock of red hair still existed, hidden in his white hair. Minos, King of Crete attacked Megara but Nisus knew he could not be beat because he still had his lock of red hair. His daughter, Scylla, fell in love with Minos and proved it by cutting the red hair off her father's head. Nisus died and Megara fell to Crete. Minos killed Scylla for disobeying her father. She was changed into a seabird, relentlessly pursued by her father, who was a sea eagle. He had one son: Amphinomus. (Ovid VIII, 35).
- The other was a son of Hyrtacus and friends with Aeneas and Euryalus. Euryalus died during a nocturnal raid on the Rutulians. (Virgil V, 294; IX, 199, 234.)
