region,
part a knowledge domain that you are interested in or are communicating about; "it was a limited realm of discourse"; "here we enter the region of opinion"; "the realm of the occult"
surface the outer boundary of an artifact or a material layer constituting or resembling such a boundary; "there is a special cleaner for these surfaces"; "the cloth had a pattern of red dots on a white surface"
Adjective
inside -
relating to or being on the side closer to the center or within a defined space; "he reached into his inside jacket pocket"; "inside out"; "an inside pitch is between home plate and the batter"
outside originating or belonging beyond some bounds:"the outside world"; "outside interests"; "an outside job"
internal happening or arising or located within some limits or especially surface; "internal organs"; "internal mechanism of a toy"; "internal party maneuvering"
inside -
away from the outer edge; "an inner lahne"; "the inside lane"
inside -
being or applying to the inside of a building; "an inside wall"
inside -
confined to an exclusive group; "privy to inner knowledge"; "inside information"; "privileged information"
inside -
The side of a curved road, racetrack etc. that has the shorter arc length; the side of a racetrack nearer the interior of the course or some other point of reference.