run out of
Exhaust a supply or quantity of, as in We're about to run out of coffee and sugar. This expression, dating from about 1700, can be used both literally and figuratively. Thus run out of gas may mean one no longer has any fuel, but it has also acquired the figurative sense of exhausting a supply of energy, enthusiasm, or support, and hence causing some activity to come to a halt. For example, After running ten laps I ran out of gas and had to rest to catch my breath, or The economic recovery seems to have run out of gas. On the other hand, run out of steam, originally alluding to a steam engine, today is used only figuratively to indicate a depletion of energy of any kind.