Pushing the envelope: 1. Move a piece of stationery across the table; push the boundaries of what is possible, from the aeronautics jargon referring to graphs of aircraft tolerance. 2. Another cracker from the kit box of oleaginous executives who wished they had become a Top Gun pilot but never had the skill; notional envelope used to denote Mach number or speed ratio a pilot or plane can endure before passing out or self-destructing; ludicrously applied to the world of business, populated as it is by flabby, Terylene-suited men slumped in warehouses, rather than an elite squad of finely-tuned pilots. (see Crash and burn; Flying unstable; Maxed out; Needle, moving the; Needle, pushing the; Wheels coming off)