Sea caves are natural formations that can be found along the coastlines, often created through the erosive forces of the sea. Synonyms for the term 'sea cave' include grotto, cavern, rock shelter, and sea arch. Grotto is derived from the Italian word grotta, meaning 'cave', and is often used to describe a sea cave that is above the waterline. Cavern is a term that is commonly used to describe a large, deep underground area. Rock shelter refers to a shallow cave-like formation that is created by a rocky overhang. Lastly, a sea arch is a type of sea cave that has been formed through the natural erosion of a rock formation into an arch shape.