Used other than figuratively or idiomatically: see front, end.
That part of a hardware or software system that is conceptually closest to the user; the user interface.
Outward or external appearance.
The outside hull of a tangible object.
The overside or up-side of a flat object such as a table, or of a liquid.
The locus of an equation (especially one with exactly two degrees of freedom) in a more-than-two-dimensional space.
To apply a surface to something.
To make (information or facts) known.
To become known or apparent; to appear or be found.
To provide something with a surface.
To bring to the surface.
To come out of hiding.
To work a mine near the surface.
To rise to the surface.