aerogram

aero- +‎ -gram

aerogram (plural aerograms)

1. (dated) A wireless message.
   • 1890, “Our New Satellite”, in English Mechanic and World of Science: With which are Incorporated "the Mechanic", "Scientific Opinion," and the "British and Foreign Mechanic.", volume 50, E. J. Kibblewhite, page 499:

     An aërogram to the Examiner yesterday from Quito announced the success of the second attempt, and details of the achievement were at once secured.

2. (dated, rare) A telegram whose transmission included at least one segment sent via airplane.
   • 1919, The Electrical Review‎, volume 84, H. Alabaster, Gatehouse & Company, page 538:

     Mr. Holt Thomas gave some details of a projected scheme of communication which combined the telephone or telegraph with the aeroplane. Messages sent by the system would be described as aerograms.

3. A thin piece of foldable and gummed paper for writing a letter and serving as its own envelope for transit via airmail.
4. (medicine, rare) A pneumogram.
   • 1935, William Alexander Newman Dorland and E. C. Miller, Illustrated medical dictionary‎, 17^h edition, page 53:

     aerogram 1. A roentgenogram of an organ afer it has been injected with air; also called pneumogram.