Why do the British call it an
aeroplane, while Americans use the slightly different
airplane?
Aeroplane comes from Greek
aéro- "air" +
-planos "wandering" and was first used in reference to air travel in 1873.
The American spelling and pronunciation
airplane did not gain popularity in the States until 1907, at which point it replaced the original
aeroplane. Such divergence is natural and to be expected when two dialects are largely isolated from one another geographically.
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