An inland sea, a loch, a lough or a lake.
A lake is a large body of water surrounded by land.
a large body of water surrounded by land.
Lake
A lake.
Peninsula
lake
ocean
Yes, or - if it is very large - a continent.
A lake is a large body of water that is surrounded by land a body of (usually fresh) water surrounded by land
A peninsula is a piece of land that is nearly surrounded by water but connected to mainland via an isthmus, a large mass of land projecting into a body of water, a piece of land surrounded by water on 3 sides, or it could be a narrow piece of land jutting out into the sea
A lake, or an inland sea.
A bay is a body of water that is partly enclosed by land (and is usually smaller than a gulf).