surface
n
1 covering, exterior, façade, face, facet, outside, plane, side, skin, superficies (rare) top, veneer
2 on the surface apparently, at first glance, ostensibly, outwardly, seemingly, superficially, to all appearances, to the casual eye
adj
3 apparent, exterior, external, outward, superficial
vb
4 appear, come to light, come up, crop up (informal) emerge, materialize, rise, transpire