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Webster 1913 Edition

(prŏg′nȧ-thŭs)

Adj.

[Gr.

πρό

before +

γνάθοσ

the jaw]

(Anat.)

Having the jaws projecting beyond the upper part of the face; – opposed to

orthognathous

. See

Gnathic index

, under

Their countenances had the true

prognathous

character.

Kane.

prognathous ‎(comparative more prognathous, superlative most prognathous)

Having jaws that project forward more than is usual.
- 1918, Edgar Rice Burroughs, “VIII”, in The Land That Time Forgot:
  A huge brute with thick lips and prognathous jaw stood at her shoulder. He was talking loudly and gesticulating wildly.
- 2013, Adam Slipinski, Australian Beetles Volume 1: Morphology, Classification and Keys:
  Phycosecids are small, ovate, convex beetles with a prognathous head, partly covered by a semicircular projection of the pronotum and a dorsal vestiture of whitish scales or scalelike setae.

with jaws projecting forward