has_2D_boundary

has boundary

a relation between a material entity and a 2D immaterial entity (the boundary), in which the boundary delimits the material entity

A 2D boundary may have holes and gaps, but it must be a single connected entity, not an aggregate of several disconnected parts.

Although the boundary is two-dimensional, it exists in three-dimensional space and thus has a 3D shape.

my body has 2D boundary the surface of my skin

http://purl.obolibrary.org/obo/RO_0001901