To act or behave recklessly and/or fearlessly, with no sense of restraint or propriety. (An older variant of the now more common "throw caution to the wind(s).") After my father won a bit of money at the race tracks, he began throwing discretion to the winds and ended up gambling away everything we had. You can't live life completely reserved, you know—you've got to throw discretion to the wind every now and then.