under one's own steam

A reference to the operation of a steam engine: see sense 1.^[1]

• (Received Pronunciation) IPA^(key): /ˌʌndə ˈwʌnz əʊn ˈstiːm/
• (General American) IPA^(key): /ˌʌndɚ ˈwʌnz oʊn ˈstim/

• Audio (General Australian):

  (file)

• Rhymes: -iːm
• Hyphenation: un‧der one's own steam

under one's own steam

1. (nautical, rail transport) Of the movement of a locomotive or a watercraft: by means of the power of its own engines (originally steam engines), rather than pulled or pushed by another vehicle.
   • 1915, Victor Appleton [pseudonym], “Almost an Accident”, in The Moving Picture Boys at Panama: Or Stirring Adventures along the Grand Canal, New York, N.Y.: Grosset & Dunlap, →OCLC, page 106:

     Now the tug no longer moved under her own steam, nor had it been since coming alongside the wall of the central pier. For all vessels must be towed through the lock basins, and towed not by other craft, but by electric locomotives that run alongside, on top of the concrete walls.

   • 1941 April, “Notes and News: Railwaymen and Snow”, in The Railway Magazine, London: Tothill Press, →ISSN, →OCLC, page 178:

     By Tuesday evening the track had been cleared to the three snowbound engines, and the following day, under their own steam, they were moved away; the business of relighting their fires and raising steam in such conditions is better imagined than described.

2. (idiomatic, figuratively)
   1. Using one's own resources; independently, unaided.
      • 1987 August 18, “At the Fringe in Edinburgh, theater in crypt and streets”, in The New York Times‎, New York, N.Y.: The New York Times Company, →ISSN, →OCLC, archived from the original on 8 January 2021, section C, page 17, columns 1–2:

        "People come at their own risk, at their own expense, under their own steam," said Mhairi McKenzie-Robinson, chief administrator of the Fringe [Edinburgh Fringe Festival].

      • 2008 September 9, Josh Quittner, “Steve Jobs: Not Dead Yet”, in Time‎, New York, N.Y.: Time Warner Publishing, →ISSN, →OCLC, archived from the original on 10 September 2008:

        After the event, [Steve] Jobs even briefly joined the media where Apple's new product line was being shown. He walked under his own steam, of course, easily and without any apparent discomfort. […] Whether Jobs's health is in decline or not, it's undeniable that the past five years have been the most fertile of his magnificent career.

   2. At one's own initiative; of one's own accord, unbidden, unprompted.
      • 1980, Charlotte Vale Allen, Promises, Norwalk, Conn.: Island Nation Press, published 1999, →ISBN, page 265:

        I'd been wanting her to go for a long, long time, hoping she'd get up the gumption to do it under her own steam so I wouldn't have to make a scene about it.

• “under one's own steam, phrase”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.