General:
* Islets: This is the most common synonym, referring to small islands.
* Cays: This term often refers to small, low-lying islands made of coral or sand.
* Keys: Similar to "cays," but sometimes implies a specific type of island formation.
* Shoals: These are submerged sandbars or reefs that can sometimes emerge above water as small islands.
* Sandbars: This specifically refers to a long, narrow ridge of sand above the water.
* Atolls: Ring-shaped islands formed by coral reefs surrounding a lagoon.
More Specific:
* Motu: This Polynesian term refers to a small, low-lying island typically found in an atoll.
* Ait: This is a Micronesian word for a small island or islet, often used in the context of a lagoon.
Literary or Poetic:
* Rock: This can be used metaphorically for a small island, especially if it is rocky.
* Dune: This evokes an image of a sandy, low-lying island.
* Spit: This implies a narrow strip of land extending out from a larger landmass.
The best synonym will depend on the specific context of your writing. Consider the size, shape, and location of the island, as well as the tone and style of your writing.