Meaning

noun the shore of a sea or ocean

verb move effortlessly; by force of gravity

noun a slope down which sleds may coast

originFrom Middle English costeien (“to travel along a border or coast; to go alongside (something), skirt; to accompany, follow; to travel across, traverse; to be adjacent to, to border;”) [and other forms], from Anglo-Norman [Term?], Old French costoier (“to be at the side of”) […] (modern…

Etymology from Wiktionary, CC BY-SA 3.0