P meaning in Earth Science ?

A peninsula (Latin: paeninsula from paene 'almost' and insula 'island') is a landform surrounded by water on most of its border while being connected to a mainland from which it extends. The surrounding water is usually understood to be continuous, though not necessarily named as a body of water. A river which courses through a very tight meander is also sometimes said to form a "peninsula" within the (almost closed) loop of water.

There is no precise definition distinguishing peninsulas from less prominent extensions, and extensions conventionally considered peninsulas are not always named as such; they can also be referred to as a headland, cape, island promontory, bill, point, fork, or spit. A point is generally considered a piece of land projecting into a body of water that is less prominent than a cape. The area of peninsulas can range from tiny to very large.

In English, the plural forms of peninsula are peninsulas or “sular”