sea

US /siː/
UK /siː/
"sea" picture
1.

the expanse of salt water that covers most of the earth's surface and surrounds its landmasses

:
The ship sailed across the vast sea.
We spent our vacation by the sea.
2.

a large area of fresh water; a lake

:
The Caspian Sea is actually the world's largest inland body of water.
They sailed their small boat on the Dead Sea.
3.

a large amount or number of something

:
There was a sea of faces in the crowd.
He inherited a sea of troubles from his predecessor.