"a nose turned upwards at the tip," 1778, from pug (n.) based on fancied similarity to the nose of either the monkey or the dog. Related: Pug-nosed (1791). Pug-face is attested by 1768.
"soar, glide on motionless wings," early 15c., planen, from Old French planer "to hover (as a bird), to lie flat," from plan (n.) "plane," or perhaps via Medieval Latin; in either case from Latin planum "flat surface" (from PIE root *pele- (2) "flat; to spread"), on notion of bird gliding with flattened wings. Of boats, etc., "to skim over the surface of water," it is attested by 1913. Related: Planed; planing.
1831, "heavyweight horseman," later "boxer or wrestler of a certain weight" (1896), from earlier welter "heavyweight horseman or boxer" (1804), possibly from welt (v.) "beat severely" (c. 1400).
... but at the end of the first German mile, Nature gave way, and this excellent mare was obliged to "knock under" to the extraordinary exertions she had made, and to the welter weight she carried, upwards of 13 stone. [The Sporting Magazine, September 1831]
1866, originally in reference to surfaces such as shell casings of beetle wings, from French aéroplane (1855), from Greek-derived aero- "air" (see air (n.1)) + stem of French planer "to soar," from Latin planus "level, flat" (from PIE root *pele- (2) "flat; to spread").
The word was later extended to the wing of a heavier-than-air flying machine. The use of the word in reference to the machine itself is first attested 1873 and probably is an independent coinage in English. Also see airplane. Ancient Greek had a word aeroplanos, but it meant "wandering in the air," from planos "wandering" (see planet).