How much is a cubic foot?

A cubic foot -- cu.ft. or ft3 -- is a unit of volume. It is the space occupied by a cube whose edges are one linear foot long. If by "terms" you mean "units," then there is only one term -- the foot -- which is raised to the power of three (that is, it is cubed). Since the foot is a fundamental unit that cannot be decomposed, you can say there is only one term.