Since contact lenses are corrective lenses for contact with the eye, I presume you mean the general case with optics.
The answer is that lenses can be in contact with each other and often are. But it...
The numbers on your prescription will correspond to the following: - Dia - Diameter - OS - Left Eye - OD - Right Eye - BC - Base Curve - OU - Both Eyes - Axis - (Toric lenses only) - Cyl - Cylinder...