seaboard

noun

1. the line where land and sea meet.
2. a region bordering a seacoast: the Eastern seaboard.

adjective

3. bordering on or adjoining the sea.

noun

1. 1. land bordering on the sea; the seashore
   2. (as modifier)seaboard towns

n.“seaward side of a ship,” late 15c., from sea + board (n.2).