coast . (a) A strip of land of indefinite width (may be many kilometers), bordering the ocean, that extends from the low-tide line inland to the first major change in landform features. Note that lakes and rivers have shores, while coasts are generally understood as bordering only oceans. (b) The part of a country regarded as near the coast, often including the whole of the coastal plain; a littoral district having some specific feature, such as the Gold Coast. Adj: coastal.