Meaning

noun the outer boundary of an artifact or a material layer constituting or resembling such a boundary

noun the extended two-dimensional outer boundary of a three-dimensional object

noun the outermost level of the land or sea

originEtymology tree Middle French surfacebor. English surface Borrowed from Middle French surface. By surface analysis, sur- + face. Doublet of superficies.

Etymology from Wiktionary, CC BY-SA 3.0