Source : Webster's Revised Unabridged Dictionary (1913)

Coastal \Coast"al\, a.
   Of or pertaining to a coast.

Source : WordNet®

coastal
     adj 1: of or relating to a coast; "coastal erosion"
     2: located on or near or bordering on a coast; "coastal
        marshes"; "coastal waters"; "the Atlantic coastal plain"
        [ant: {inland}]