peter out

Dwindle or diminish and come to an end, as in Their enthusiasm soon petered out. The origin of this usage is unknown, but one authority suggests it may refer to the apostle Peter, whose enthusiastic support of Jesus quickly diminished so that he denied knowing him three times during the night after Jesus's arrest. [Mid-1800s]

Definition: dwindle, decrease
Antonyms: develop, grow, increase

Like the gold in the hills of California, American English had begun to peter out by 1854, as in the novel Puddleford and Its People by Henry H. Riley, published that year: "He 'hoped this 'spectable meeting war n't going to Peter-out.'" Abraham Lincoln used the phrase too, according to an 1865 biography: "The store in which he clerked was 'petering out'--to use his own expression."

Peter out, as a literal mining term and a figure of speech meaning "dwindle" or "give out," derives from peter, attested as early as 1846 in Quincy, Illinois: "When my mineral petered why they all Petered me. If so be I gets a lead, why I'm Mr. Tiff again." Where that peter came from, no one knows. In any case, plain peter soon petered out in favor of peter out, as in the words of Riley and Lincoln, and this 1884 dialogue from Century Magazine: "We'll have a blank good time,...anyhow, as long as the whisky don't peter out."

A technical mining definition of peter out appears in the Century Dictionary (1889-91): "to split up into branches and become lost: said of a vein which runs out or disappears, so that it can no longer be followed by the miner." But Americans have kept peter out from petering out by using it in all sorts of contexts having nothing to do with mines; a feud, a road, a river, a crop, a hurricane, even a Boom (1871) for a political candidate all can be said to peter out.

The verb has 2 meanings:

Meaning #1: end weakly
  Synonyms: taper off, fizzle out, fizzle

Meaning #2: use up all one's strength and energy and stop working
  Synonyms: poop out, run down, run out, conk out