coastline
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.”
“The same stretch of coastline was struck by a similarly powerful earthquake in December 1992, when the quake and the tsunami it triggered killed more than 2,500 people on Flores.”
“Back at the end of June, the two teenagers had gone to the beach on Venezuela's Caribbean coastline.”
From coast + line.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.