ppl. a. (In attrib. use u·nderhung.) [UNDER-1 4 a.]
1. Having the lower jaw projecting beyond the upper, or coming unusually far forward.
1683. Lond. Gaz., No. 1800/4. Lost…, a red fallow Colour’d dun Bull-Bitch,… with a black Muzle under-hung.
1774. Goldsm., Nat. Hist., II. v. 91. Those whose upper and under row of teeth are equally prominent, and strike directly against each other, are what the painters call under-hung.
c. 1815. Jane Austen, Persuas., xv. He … must lament his being very much under-hung, a defect which time seemed to have increased.
1861. Hughes, Tom Brown at Oxf., ii. [He] had got the trick which many underhung men have of compressing his upper lip.
b. Projecting beyond the upper jaw.
1809. Malkin, Gil Blas, XI. iv. ¶ 4. Wagging his under-hung jaw in a paroxysm of humour-stricken ecstasy.
1868. Darwin, Anim. & Pl., I. i. 38. Bull-dogs … after two or three generations … lose the under-hung character of their lower jaws.
1899. Allbutt’s Syst. Med., VIII. 235. The jaw heavy and sometimes underhung.
2. Mech. Suspended on an underlying support; spec. of a sliding-door which moves on a rail placed below it. (Opposed to OVERHUNG ppl. a. 3.)
1855. D. K. Clark, Railway Mach., I. 207/1. Engine Cylinders underhung, castings in two pieces bolted together.
