A bit of trivia, Steve. Do you know that here in the US we used the French aerodrome and aeroplane until the early 1950s, or so?
I used to fly small planes and got a pilot’s license at 19, which is why I have an interest in aircraft, but I haven’t flown a plane in 41 years, but yes, I knew of the word aerodrome. That used to appear on our old maps. I have seen airplane spelled aeroplane, but that’s more of a minor spelling and pronunciation change, wouldn’t you say? Not a complete dropping of the word. Aerodrome also hasn’t really disappeared, it’s just become part of pilot jargon, as far as I can tell, and I think some pilots may still use it today.
But, English has no main language authority, so it’s hard to track language trends in English except in the broad sense, like looking at a 1611 King James Bible, or something. We all know people don’t talk like that anymore.
But, you are right. There are a few old words, like 1950s and earlier words that have long disappeared. Nothing comes to mind off the top of my head, except for a few words from the 60s like groovy, but those were more teenager slang words.