Pterygoid bone

The pterygoid is a paired bone forming part of the palate of many vertebrates, behind the palatine bones.

Skull diagram of Champsosaurus, showing the pterygoid bone in red-violet (visible in inferior view at lower right and posterior to the ectopterygoid bone in lateral view at top)

It is a flat and thin lamina, united to the medial side of the pterygoid process of the sphenoid bone, and to the perpendicular lamina of the palatine bone.