Abarim Publications' online Biblical Greek Dictionary
The noun νησος (nesos) means island. It's not clear where this word may have come from, and none of the common suggestions is very satisfying. Here at Abarim Publications we don't know either, but if we were to guess we would guess a link with the verb νεομαι (neomai), to go back or return, and particularly the derived noun νοστος (nostos), a return home.
This latter noun occurs frequently in Homer's Odyssey, for obvious reasons. A famous secondary work of later poets was entitled Nostoi, or Journeys Home, which told of other Greek heroes trying to make it back to Greece after the sacking of Troy.
The name Peloponnese, of the southern half of Greece, means island of Pelops (Pelops + nesos), and Pelops was a famous king and grandfather of Agamemnon and Menelaos; both major players in the Iliad. Another major Homeric character is Nestor, former Argonaut with Jason and king of Pylos, a city on the southern coast of the Peloponnese. His name, Νεστωρ (Nestor) is thought to derive from νοστος (nostos), a return home.
These words all derive from the PIE root "nes-", to return home safely (from which German gets its verb genesen, to recover from an illness), and may even relate to the noun ναος (naos), temple, and ναιω (naio), to dwell (to be home at).
The Greeks were notorious seafarers but in the Hebrew mind, the solid footing of dry land related to certainty and wisdom, whereas sea related to uncertainty and madness. That means that to the Hebrews, an island was an enclave of reason in an ocean of folly (see for more on the cognitive aspect of the hydrological cycle our article on the noun νεφελη, nephele, cloud).
Our noun νησος (nesos), island, occurs 9 times, see full concordance, and from it derives.
- The noun νησιον (nesion), which is a diminutive of the former and means little island (Acts 27:16 only).