In
Computer Graphics a
mesh is a
surface, usually
piece-wise linear, describing the object to be
rendered.
It's quite common, for instance, to describe a three-dimensional object as a set of
vertices, and then defining the neighbourhood relations between them: in this way you get a mesh.
Another piece of information: at the last
SIGGRAPH, a whole session was devoted to
subdivision, an
algorithm to
iteratively refine a mesh, increasing the number of
polygons belonging to the
surface.