to not expect something to happen quickly She wants the company to apologize for damaging her reputation, but she isn't holding her breath.
Usage notes: often used in the form don't hold your breath: If you're waiting for the next big cut in computer prices to buy that powerful new machine, don't hold your breath.
Etymology: based on the idea that it will take longer for the thing you are waiting for to happen than the amount of time you can hold you breath(stop breathing)