Often one confuses the term BIOS and CMOS since most of the instructions roughly mention BIOS setup or CMOS setup. The Setup of BIOS and CMOS are same. But in terms of motherboard, it is not same.
BIOS is a set of computer instructions in firmware that control input and output operations. BIOS contains instructions on how the computer boots and stores the system configuration details. It is also responsible to update the date and time automatically even when the computer is switched off. Moreover, it can be modified or updated only with the BIOS updates.
CMOS - Complementary Metal Oxide Semiconductor. CMOS contains system settings and it is powered by a CMOS battery. It can also be modified and changed be entering the CMOS setup during your
computer start-up by pressing function keys (Differ for different motherboards).
Now I think you may be clear about the difference between these two similar terms. Now coming to the point, you can refer the setup as CMOS setup which is more appropriate than calling BIOS setup.