at once

• attonce (obsolete)

From at + once.

• (UK) IPA^(key): /ət ˈwʌns/

• Audio (General Australian):

  (file)

at once (not comparable)

1. (obsolete) In one group; together.
   • 1526, [William Tyndale, transl.], The Newe Testamẽt […] (Tyndale Bible), [Worms, Germany: Peter Schöffer], →OCLC, Luke xiiij:[18], folio cj, recto:

     And they all atonce begane to make excuſe. The fyrſt ſayd vnto him: I have bought a ferme / and I muſt nedes goo and ſe it / I praye the have me excuſed.

   • 1590, Edmund Spenser, “Book III, Canto IV”, in The Faerie Queene. […], London: […] [John Wolfe] for William Ponsonbie, →OCLC:

     Those two great champions did attonce pursew / The fearefull damzell with incessany payns [...].

2. At the same time; simultaneously; together.

   Can you pat your head and rub your belly at once?
   He tried to eat four cookies at once.

   • 2013 August 10, Lexington, “Keeping the mighty honest: A new wave of press barons should not allow newspapers to become niche products”, in The Economist‎^[1], volume 408, number 8848:

     The [Washington] Post's proprietor through those turbulent [Watergate] days, Katharine Graham, held a double place in Washington’s hierarchy: at once regal Georgetown hostess and scrappy newshound, ready to hold the establishment to account.

   • 2014 September 26, Tom Payne, “Sapiens: a Brief History of Humankind by Yuval Noah Harari, review: 'urgent questions' [print version: The story of our species, 27 September 2014, p. R32]”, in The Daily Telegraph (Review)‎^[2]:

     [T]he book, constructed in short, lucid episodes, can be satisfyingly read as a sequence of provocative talks, at once well informed and vatic.

3. Immediately; now; right away.

   Tell the doctor to come at once. She is having a baby.

   • 1897 December (indicated as 1898), Winston Churchill, chapter IV, in The Celebrity: An Episode, New York, N.Y.: The Macmillan Company; London: Macmillan & Co., Ltd., →OCLC:

     Mr. Cooke at once began a tirade against the residents of Asquith for permitting a sandy and generally disgraceful condition of the roads. So roundly did he vituperate the inn management in particular, and with such a loud flow of words, that I trembled lest he should be heard on the veranda.

   • 1918, W[illiam] B[abington] Maxwell, chapter III, in The Mirror and the Lamp, Indianapolis, Ind.: The Bobbs-Merrill Company, →OCLC:

     One saint's day in mid-term a certain newly appointed suffragan-bishop came to the school chapel, and there preached on “The Inner Life.”  He at once secured attention by his informal method, and when presently the coughing of Jarvis […] interrupted the sermon, he altogether captivated his audience with a remark about cough lozenges being cheap and easily procurable.

   • 1960 March, “Talking of Trains: The Slough derailment”, in Trains Illustrated, page 132:

     Sparks from the derailed bogie of the train were first noticed by the signalman at Slough West box, who immediately sent to Slough Middle box the "Stop and Examine" signal, followed at once by "Obstruction Danger" when he realised that the coach was derailed.

   • 1963, Margery Allingham, chapter 19, in The China Governess: A Mystery, London: Chatto & Windus, →OCLC:

     As soon as Julia returned with a constable, Timothy, who was on the point of exhaustion, prepared to give over to him gratefully. The newcomer turned out to be a powerful youngster, fully trained and eager to help, and he stripped off his tunic at once.

• Acteon, encoat, octane