-gnathycomb. form
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Primary stress is attracted to the syllable immediately preceding this combining form and vowels may be reduced accordingly; see e.g.
prognathy n.Origin: A borrowing from Greek, combined with an English element. Etymons: Greek γνάθος , -y suffix3.
Etymology: < ancient Greek γνάθος jaw (see -gnath comb. form) + -y suffix3. Compare German -gnathie . Compare -gnathism comb. form.Found in a very small number of formations in the late 19th cent., e.g. mesognathy n., prognathy n.
Chiefly
Physical Anthropology.
This is a new entry (OED Third Edition, November 2010; most recently modified version published online December 2018).