• Webster's Revised Unabridged Dictionary
    • a Orbitosphenoid (Anat) Of or pertaining to the sphenoid bone and the orbit, or to the orbitosphenoid bone.
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Century Dictionary and Cyclopedia
    • orbitosphenoid Orbital and sphenoidal; forming a part of the sphenoid bone in relation with the orbit of the eye.
    • n orbitosphenoid In anatomy, a bone of the third cranial segment, of the skull, morphologically situated between the presphenoid and the frontal, and separated from the alisphenoid by the orbital nerves, especially the first division of the fifth nerve. It is commonly united with other sphenoidal elements; in man it constitutes the lesser wing of the sphenoid, or process of Ingrassias, and bounds the sphenoidal fissure in front, forming a part of the bony orbit of the eye. See cuts under Crocodilia, Gallinæ, orbit, skull, and sphenoid.
    • n orbitosphenoid In ichthyology, a bone anterior to the alisphenoid and usually forming part of the orbital septum. It is common only among the soft-rayed fishes. The orbitosphenoid of Owen is the alisphenoid of Huxley and Parker.
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Webster's Revised Unabridged Dictionary
Orbit, + sphenoid,


In literature:

The orbitosphenoids develop separately from it.
"Form and Function" by E. S. (Edward Stuart) Russell
Thus the orbitosphenoids remain distinct from the presphenoid.
"The Cambridge Natural History, Vol X., Mammalia" by Frank Evers Beddard