fossette
/fɒˈsɛt/(also fosette)
noun
Anatomy, Zoology, and Palaeontology. A small pit, depression, or fossa in the surface of a solid structure, as in the crown of a tooth or the cuticle of an arthropod.
Origin
Early 19th century. From French fossette small pit or depression in the surface of a solid structure, kind of ulcer of the cornea (1782 or earlier; earlier in senses ‘small depression’, ‘dimple’) from fosse + -ette.