The Collaborative International Dictionary of English v.0.48:
Pterygoid \Pter"y*goid\, a. [Gr. ?, ?, a wing + -oid.] (Anat.)
(a) Like a bird's wing in form; as, a pterygoid bone.
(b) Of, pertaining to, or in the region of, the pterygoid
bones, pterygoid processes, or the whole sphenoid bone.
-- n. A pterygoid bone.
Pterygoid bone (Anat.), a bone which corresponds to the
inner plate of the pterygoid process of the human skull,
but which, in all vertebrates below mammals, is not
connected with the posterior nares, but serves to connect
the palatine bones with the point of suspension of the
Pterygoid process (Anat.), a process projecting downward
from either side of the sphenoid bone, in man divided into
two plates, an inner and an outer. The posterior nares
pass through the space, called the pterygoid fossa,
between the processes.