Upper lip

The upper lip corresponds to the upper part of the lips. It joins the lower lip by a corner defining the angle of the mouth. It is crossed in the middle by a vertical median furrow, the philtrum.

The upper lip is always larger than the lower lip, which it overlaps or covers to a greater or lesser extent. The difference in volume is fairly small in equids and small ruminants, negligible in humans; on the other hand, it is significant in pigs, cattle, carnivores, and rabbits.