Just a random, relatively unimportant question... What would be the correct term (if there is one) for a NIC in its regular mode? Any time I see promiscuous mode is discussed, there's never a term given for the normal state of operation.

A NIC running in something other than promiscuous mode is generally referred to as "non-promiscuous." You usually don't use this term unless it's in the context of supporting or using promiscuous mode in an effort to differentiate between the two. If you don't have a need to define a NIC as promiscuous, then you're almost never describing a NIC as non-promiscuous; there's just no reason to put it into that context, otherwise.

This makes sense, thank you.