Coast
COAST. This term is found in KJV in an archaic expression from the Lat. costa meaning “rib” or “side” and frequently tr. the Heb. word גְּבוּל, H1473, “border.” Today the word is used only in reference to the border of the sea, but in the time of the KJV it was used of any border of a nation or people or town (cf. Matt 2:16). A Christmas carol of a later period obviously misunderstood this text and has ships sailing into Bethlehem, a geographical impossibility. In places where the border was a seacoast, the term “coast” would be appropriate.
The RSV uses the word “coastland,” tr. the Heb. word אִי, H362, which usually means “island” (Gen 10:5; Ps 97:1; Jer 47:4; etc.).
International Standard Bible Encyclopedia (1915)
See Isle.