let slip

let (something) slip

To accidentally or inadvertently reveal some secret or important piece of information. I can't believe your sister let news of our engagement slip in front of your parents! The agent, under the influence of a powerful truth serum, let slip the names of other operatives working covertly in the area.
See also: let, slip
Farlex Dictionary of Idioms.

let something slip (out)

Fig. to reveal a secret carelessly or by accident. I didn't let it slip out on purpose. It was an accident. John let the plans slip when he was talking to Bill.
See also: let, slip
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

let slip

1. Also, let slip or slide by ; let slide. Miss an opportunity; waste time. For example, We forgot to buy a ticket and let our big chance slip by, or He let the whole day slide by. The first term dates from the mid-1500s, the variant from the late 1500s.
2. Also, let slip out. Reveal something, usually inadvertently, as in He let it slip out that he had applied for the vacant position. [Mid-1800s]
3. let slip through one's fingers. Fail to seize an opportunity, as in We could have won the trophy but we let it slip through our fingers. [First half of 1600s]
See also: let, slip
The American Heritage® Dictionary of Idioms by Christine Ammer.

let slip

To say inadvertently.
See also: let, slip
American Heritage® Dictionary of the English Language, Fifth Edition.
See also:
  • let (something) slip
  • let it slip
  • let slip something
  • let something slip
  • let fall something
  • let (something) fall
  • a slip of the tongue
  • let (something) drop
  • let drop
  • let it
References in periodicals archive
But in The Washington Post interview he let slip that he personally thinks Iran has that goal.
As simple and even rudimentary as the story appears to be, scraps of information let slip throughout make us question exactly how long it has taken for Keane's marriage and sanity to crumble so totally.
It invites us to let slip the moorings of rampant self, and gently, gratefully turn toward completion.
A few of the poems could have been cut to let slip the beauty of her life experiences.
Moments before Ahmed successfully bid 875,000gns for a colt by Barathea, Mulhall let slip that Royal Anthem is close to retirement, although stud plans are in the process of being finalised for the injury-stricken colt.
Sun CEO Scott McNealy, able as always to spot a PR opportunity, let slip the name 'Corona' to analysts last week, and allowed himself to be gently chastised by his publicity department.
CNN, ever midul of literary precedent in White House matters, heard "dachshunds of war" and pondered if this could be a condign allusion to "cry 'Havoc]' and let slip the dogs of war"--the kind of thing regularly bruited about the green quadrangles of Yale.
Totten let slip a 3-2 lead in a 4-3 defeat to Northern Irishman Joe Swail while Sharav mustered a top break of 14 in a 4-0 whitewash at the hands of Welshman Matthew Stevens.
Did she inadvertently let slip that in future we will have fortnightly collections if she gets her way, and that was the plan all along to save money?
THE NEW SAINTS suffered only their second defeat of the season when they let slip a half-time lead to go down 2-1 at Connah's Quay.
Which town was the Duchess of Cambridge visiting on Tuesday when she reportedly let slip to a member of the public that she and the Duke of Cambridge are expecting a girl?
Summary: Michael Caine has let slip that he thinks The Dark Knight Rises will not be quite as good as Cars 2.
Liberty is stunned when she is offered a performance slot at T4 on the Beach, and asks Theresa to join her - but Ethan is concerned that the pair might let slip their secrets during the trip, so offers to go along for the ride.
Corden's guest appearance was meant to be a secret but the comic apparently let slip to a fan on a train to the capital as he learnt his lines.
London, July 7 (ANI): Prince William has let slip his plans to go to Australia next year.