The shoreline is the place where a large body of water, like an ocean, lake, or river, meets the land. There are a lot of fun beaches along the Atlantic shoreline.
You can use the noun shoreline to talk about the strip that marks the boundary between land and water, whether it's at the edge of an ocean, sea, lake, or river. While the word "coast" refers specifically to the ocean, shoreline or shore can be used for any body of water. The word was first coined in the mid-1800's by geographers, and its root is the Germanic schor, "shore, coast, or headland."