e. before (one) can say knife: very quickly or suddenly. Also while (one) would say knife. colloquial.
1874 M. Clarke His Nat. Life II. iii. viii. 170 He was over the wall before you could say ‘knife’.
1880 L. Parr Adam & Eve xxxii. 443 'Fore I could say knife he was out and clane off.
1893 R. Kipling Many Inventions 334 We'll pull you off before you can say knife.
1922 J. Joyce Ulysses ii. viii. [Lestrygonians] 153 Toss off a glass of brandy neat while you'd say knife.
1954 A. Macrae Both Ends Meet in Plays of Year X. 509 With a couple like that you'll be in a lawsuit before you can say ‘knife’.
1973 M. Muggeridge Infernal Grove i. 71 Like alcoholics after taking the cure—never another drop; well, just a taste perhaps, and then, before you could say knife, back on the meths.
Only in before one can (also could) say Jack Robinson and variants: in a very short time; very quickly or suddenly.
1763 Beauties of all Mag. Sel. II. 81/1 Before you can say Jack Robinson, locks them fast in a square inch of paper.
1778 F. Burney Evelina III. xxi. 241 I'd do it as soon as say Jack Robinson.
1785 E. Winslow in Winslow Papers 310 Before I could say ‘Jack Robinson’.
1814 M. W. Shelley in E. Dowden Life Shelley (1887) I. 453 The white and flying cloud of noon, that is gone before one can say ‘Jack Robinson’.
1863 London Soc. Nov. 475/2 A native gentleman comes up,..gives a smart bow, and before you can say Jack Robinson, is twirling her round the room.
1903 A. Adams Log of Cowboy vii. 86 Before you could say Jack Robinson our dogies..were running in half a dozen different directions.
1949 E. Goudge Gentian Hill i. vi. 105 Her little white teeth were buried in it before anyone had time to say Jack Robinson.
2016 Nigerian Tribune (Nexis) 4 Nov. Before you can say Jack Robinson, things will begin to move for them positively.
Jack Robinson is a name present in a common figure of speech used to represent quickness. The normal usage is, "(something is done) faster than you can say Jack Robinson" or otherwise "before you can say Jack Robinson." The phrase can be traced back to the eighteenth century. The similar phrase "Before you can say 'Knife!'" dates from at least 1850, when it appeared in Charles Dickens' Household Words.
used to say that something happens very quickly:
Before you could say Jack Robinson, she'd jumped into the car and driven away.
before you can say Jack Robinson
(old-fashioned) very quickly; very soon
NOUN BRITISH INFORMAL OLD-FASHIONED
Dictionary: jack robinson
He was there before you could say Jack Robinson -- Er war in null Komma nichts da
Do MPs fit the thesis by working longer? Not at first glance. They're off to flip a few second homes before you can say knife.
And before you can say Jack Robinson you've got snappers up on ladders and behind the bushes, snapping away with even bigger lenses.
Farage has said that if Ukip fails to win a seat in the general election next year, he will quit. "Good lord, yes. I will be out the door before you can say Jack Robinson."
Before you can say the words rambling-country-pile-with-heated-pool-and-own-beach-access, you are envisaging long, lazy days incorporating idyllic group picnics on the sand...
Then before you can say Ferdinand, Woodgate and Kewell - and we can say it pretty darned quickly: Fdnwdgtkwl! - they go and do just that.
But, before you can say vocation, vocation, vocation, he's opting instead to run a named-and-shamed sink school which he himself recommended for closure. Don't you just know that those disaffected yobs will be tapping their toes to Mozart before you can say 'the CD is available at your local music store'? Amanda Redman and Clive Russell are his lieutenants.