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).
"small imaginary creature blamed for mechanical failures," oral use in R.A.F. aviators' slang from Malta, the Middle East and India is said to date to 1923. First printed use perhaps in poem in journal "Aeroplane" April 10, 1929; certainly in use by 1941, and popularized in World War II and picked up by Americans (for example New York Times Magazine April 11, 1943). Of unknown origin. OED says "probably formed by analogy with GOBLIN." Speculations in Barnhart are a possible dialectal survival of Old English gremman "to anger, vex" + the -lin of goblin; or Irish gruaimin "bad-tempered little fellow." Surfer slang for "young surfer, beach trouble-maker" is from 1961 (short form gremmie by 1962).