What’s the name of those little ridges under your nose?

Dear Cecil: In my early years, before I knew what a Kleenex was, I always knew the function of those little vertical ridges that run (ha ha) from the nose to the upper lip. Now that I have grown to the full flower of adulthood, however, I’m curious: what are those ridges really for? And what are they called? Annie, Dallas

Cecil replies:

Dear Annie:

I’m happy to hear your personal hygiene has improved so dramatically since childhood, but those little ridges are still doing the job Mother Nature intended them for–which has nothing to do with keeping your chin clean.

The ridges protect a particular sensitive spot in the skull where three bones meet, two from the sides and one from the top (the last being the device that keeps your nostrils separate). Almost every animal has them, all the way down to lizards. In humans, the ridges develop after fourteen weeks of gestation. If they fail to appear, the child is born with an unfortunate condition known as “cleft lip.”

The ridges themselves aren’t graced with a name, but the depression between them is. It’s a cute one: philtrum, from the Greek philtron, meaning “love charm.” The ancient Greeks, who liked their whimsy as much as the next civilization, thought the lips resembled the shape of Cupid’s bow; the philtrum, then, metaphorically represented the grip, the center of Cupid’s power. Or so it says here. To me, the philtrum looks more like it ought to be the arrow, but I suppose it’s a little late to start criticizing.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.