Nestor was the only son of king Nereus to survive Heracles' attack on Pylos. Rather than nao, 'to flow' as the origin for the name it would be better to consider the old element nes-, 'to save', 'bring back safely', with the 'agent' ending -tor (as in Mentor, Castor and Hector). His name will then mean 'he who brings back safely'.