Wiktionary
backface
n. (context computer graphics English) The back side of a face of a mesh, which typically will never face the camera and can thus be culled (discarded) from the list of items to be rendered.
Usage examples of "backface".
He'd have several minutes to plow through the loose sand up the backface of the dune.
He'd have several minutes to plow through the loose sand up the backface of the dune.
Knot wondered whether the backface got bored staring at the blankness, or whether it merely slept.