What is a piece of land jutting out into a lake or into the ocean and its surrounded on three sides by water?

Pieces of land that 'stick' out into the sea could be headlands, cliffs, tombolos, arches, spits etc, depending on their shape, which would be easier to determine from aerial photographs.

If the land is not a high rocky formation (cliffs), or in between sandy bays on either side (headlands), it is most likely a spit/ hooked spit.