• Webster's Revised Unabridged Dictionary
    • a Orthognathous (Anat) Having the front of the head, or the skull, nearly perpendicular, not retreating backwards above the jaws; -- opposed to prognathous. See Gnathic index, under Gnathic.
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Century Dictionary and Cyclopedia
    • orthognathous Straight-jawed; having the profile of the face vertical or nearly so, in consequence of the shortness of the jaws which constitutes orthognathism. The facial angle of an orthognathous skull is large (by whichever method it is measured), the term being more or less definitely employed as the opposite of prognathous or prosognathous, where the angle is small, or as the mean between prognathous and hyperorthognathic or opisthognathous, where the angle is excessively large. The facial angles that have been chiefly used in the definition of these terms are known as Camper's, Geoffrey Saint-Hilaire and Cuvier's, Jacquart's, and Cloquet's (which see, under craniometry). A more recent facial angle is that included between the nasio-alveolar line and a line drawn through the supra-auricular point and the inferior margin of the orbit; when this is between 83° and 90°, the skull is said to be orthognathous. The same character is also defined by means of the gnathic or alveolar index, those skulls with a gnathic index below 98 being orthognathous; between 98 and 103, mesognathous; and above 103, prognathous.
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Chambers's Twentieth Century Dictionary
    • adj Orthognathous or-thog′nā-thus straight-jawed—also Orthognath′ic
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Webster's Revised Unabridged Dictionary
Ortho-, + Gr. gna`qos the jaw
Chambers's Twentieth Century Dictionary
Gr. orthos, straight, gnathos, the jaw.


In literature:

I do not see that an orthognathous face would cost more than a prognathous face; or a good morale than a bad one.
"More Letters of Charles Darwin Volume II" by Charles Darwin

In news:

Surgical orthodontics , also known as orthognathic surgery, consists of a combination of orthodontic treatment (usually braces) and jaw surgery.
The International Journal of Adult Orthodontics & Orthognathic Surgery (Published from 1986-2002).
The International Adult Orthodontics & Orthognathic Surgery Winter Volume 17, Issue 4.