"voxels" are also a demoscene term for a method of rendering height-mapped landscapes in 3D, using a kind of raycasting technique. Technically they are "voxels", but the algorithm and their use is quite different from the sort of thing talked about here.

one thing is that only the landscape is rendered as "voxels" and it's mostly a textured height map, so it can't contain multi-level structures such as bridges, etc. it's best suited for mountain ranges and beaches and things like that.

just the term "voxels" is quite generic already, and doesn't really describe one algorithm over another, except that you're not using polygons.