peter out

From peter (“of a vein of ore: to be depleted of ore; to diminish to nothing”) + out. The etymology of peter is unknown; the following have been suggested:

• From peter (“to stop doing or saying something”).[1][2]
• Since the word was first used in mining contexts, either:[2]
  • from French péter (“to explode; to break wind, fart”); or
  • from (salt)peter, a variant of saltpetre (“potassium nitrate”), the key ingredient in gunpowder.[3]

• (Received Pronunciation) IPA^(key): /ˌpiːtɚ‿ˈaʊt/
• (General American) IPA^(key): /ˌpitɚ‿ˈaʊt/, [-ɾɚ-]

• Audio (AU)

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• Rhymes: -aʊt
• Hyphenation: pe‧ter out

peter out (third-person singular simple present peters out, present participle petering out, simple past and past participle petered out)

1. (intransitive, originally US) Synonym of peter (“to diminish to nothing, (originally) to refer to a vein of ore”)

   Synonym: spin down

   What started as a great effort ended up petering out to nothing.

   • 1883, Robert Louis Stevenson, “With the Children of Israel. I. To Introduce Mr. Kelmar.”, in The Silverado Squatters, London: Chatto and Windus, […], →OCLC, page 60:

     But the luck had failed, the mines petered out; and the army of miners had departed, and left this quarter of the world to the rattlesnakes and deer and grizzlies, and to the slower but steadier advance of husbandry.

   • 2020 November 18, Paul Bigland, “New Infrastructure and New Rolling Stock”, in Rail, Peterborough, Cambridgeshire: Bauer Media, →ISSN, →OCLC, page 49:

     Soon, the overhead wires will reach here. My only hope is that common sense prevails, and that the overhead line equipment continues its march north rather than petering out, leaving a monument to short-term thinking and a lack of vision.

• “peter out”, in Dictionary.com Unabridged, Dictionary.com, LLC, 1995–present, reproduced from Christine Ammer, The American Heritage Dictionary of Idioms, Boston, Mass.: Houghton Mifflin, 2003, →ISBN.
• Gary Martin (1997–) “Peter out”, in The Phrase Finder.