push the envelope
Definition from Wiktionary, the free dictionary
push + the + envelope, from the boundary line on a graph of an aircraft's capabilities, especially those of height and speed. Engineering jargon (of the 1950s) popularized in Tom Wolfe, The Right Stuff (1979).
- (intransitive, idiomatic) to go beyond established limits; to pioneer.
- They pushed the envelope on pricing derivatives.