uncinate process

Short definition from Wiktionary

Noun

1. 1
   A sickle-shaped extension of the ethmoid bone that projects posteroinferiorly from the ethmoidal labyrinth and articulates with the inferior nasal conchae.
2. 2
   A small portion of the head of the pancreas that extends to the back of the superior mesenteric vein and ends at the superior mesenteric artery.
3. 3
   A hook-shaped upward projection arising from each lateral border of the upper surface of the vertebral bodies of several cervical vertebrae (C3–C7).
4. 4
   A bony extension that projects caudally from the vertical segment of each rib, found in most birds, reptiles, and the early amphibian Ichthyostega.