I did a joint presentation today with a colleague who used the phrase “pushing the envelope”. I was surprised, to me the phrase is very American and she’s not. It stuck with me, it’s an expression I always meant to “look up” and I was curious about its origins.
The commonly understood meaning is going beyond usually accepted limits, and that’s the sense in which my colleague used it.
Searching around the internet for its origins I found a lot of references to aeronautics, where it refers to the combinations of parameters, such as altitude and velocity, at which flying is safe. This meaning of it was derived from a mathematical meaning ‘the locus of the ultimate intersections of consecutive curves’. If that doesn’t make it immediately clear imagine a ladder sliding down a wall, all the space that it ever occupied is, mathematically speaking, the envelope.
So in aeronautical terms “pushing the envelope” was flying in a way that pushed the aircraft beyond the limits generally accepted by mathematicians and engineers.
The term was used by technicians and pilots from 1940s onwards (at least), but it wasn’t until Tom Wolfe picked it up and used it in his book “The Right Stuff” in 1979 that it entered general use. I suspect that most people don’t realise where it originated, and couldn’t explain it if someone asked what it really meant. Did you? Is it a term you use? I’m curious.