coastline
n. countable B2 Upper Intermediate US //ˈkoʊstˌɫaɪn// UK //kˈəʊslaɪn// coast·line
n. the line where the land meets the sea. It marks the edge of the continent or island.
n. the boundary line separating land from the sea or ocean.
We walked along the coastline for an hour.
The new hotel sits right on the coastline, offering guests direct access to the beach.
Rising sea levels threaten to reshape the coastline, forcing communities to build higher walls and retreat from vulnerable shorelines.
From coast + line.