I’m having some confusion about the word nostril. I always thought it was it actual channel or cavity or opening in the nose. But some people seem to refer to the outside part of the nose (left and right) as nostril, the two “flaps” for lack of a better word.
I mean this:
I’ve always called the B part nostrils, but I actually don’t know exactly what I would call the A part.
Another word that’s also associated with this is the nose’s vestibule, but as far as I can tell that also refers to the channel or opening, not to the outer or side part.
Who can shed some light on this? What are the right terms for the A part and the B as separate things?