noun
sea
SEE/siː/
A great expanse of salt water.
Gentle waves ripple across the blue sea between rocky coastlines.

Etymology
Old English sæ covered lakes and pools as well as salt-water expanses. The selected meaning preserves its use for a large, bounded body of salt water, rather than the ancestor's broader range.
In context
It is semi-enclosed, coastal body of water, and it's connected to the open sea, and also, the salt water is diluted when fresh water from land drains into it.
More examples
- The ship crosses the Mediterranean Sea in three days.
- Many rivers carry fresh water to the sea.
- She searches the sea of faces for her brother.
Forms
sea · seas
seaward adverb — Toward or in the direction of the sea.