You are essentially correct.

Technically, it's the operating system being loaded from non-volitile memory (loads into RAM and executes there).

True firmware is a program, process, or procedure that operates from a permanant (ROM) (or semi-permanent {Flash, NVRam, static Ram}) memory location.

In the case of the Cisco equipment, the NVRAM is acting more like a hard drive or floppy to store the IOS until it's loaded into RAM for execution ... just like a spreadsheet or work processor.

The reason I said you were correct is that for the sake of discussion, when most people talk about "the firmware" for a Cisco device or module, they are generally talking about the IOS (or whatever operating code).

So, even though it is technically incorrect, IOS and "the firmware" tend to be synonymous terms for most conversations.

IOS is stored in NVRAM, but operates from RAM (in most cases), 'Firmware' is (semi-)permanent memory and the stored routines operate from there directly.

FWIW

Scott