slip-upˈslip-up noun [countable] 
Examples
We cannot afford another slip-up.► see thesaurus at mistake
ExamplesEXAMPLES FROM OTHER DICTIONARIES
Thesaurus- Despite a few unfortunate slip-ups, we finished on time.
- If we are going to win the contract, we can't afford any more slip-ups.
- This whole situation only happened because of a slip-up by the bank.
- A slip-up now and an extra, unscheduled recording break will be necessary.
- By then he had made a fatal slip-up, the court was told.
- Despite these slip-ups, I came back for another visit.
- He also looked over our shoulders while we plotted the charts, watching for any slip-ups.
- I hope it was a slip-up rather than genuine ignorance.
- It's a tough league to win and slip-ups at this stage of the season could be fatal.
- No time for slip-ups, but the odds must now be on Oxford avoiding the drop.
THESAURUS► mistake
a careless mistake: something incorrect that you accidentally do, say, or write: · a spelling mistake· I made a mistake – it should say £230, not £320.
► error formal a mistake: · an error in the report· grammatical errors· He had made a serious error on his tax form.
► misprint a small mistake in something that is printed: · There was a misprint in the article, and instead of ‘pleasant’ it said ‘pheasant’.
► typo informal a mistake in something that has been typed or printed: · I spotted a couple of typos in the letter.
► inaccuracy formal a piece of information that is not completely correct: · The report contained several inaccuracies.
► mix-up a careless mistake in which one name, time, address etc has been confused with another, so that the details of something are wrong: · There was a mix-up over the train times and I missed my train.
► slip-up a careless mistake when you are doing something: · The other team took advantage of the goalie’s slip-up.
► oversight a mistake in which you forget something or do not notice something: · Through some oversight, the brochures were not ready by the right date.
► a slip of the tongue a mistake in which you accidentally say a similar sounding word: · When I said Thursday, I meant Tuesday. It was a slip of the tongue.
► faux pas formal an embarrassing mistake in a social situation, when you do or say something that you shouldn’t: · Harris, trying to be funny, addressed the waiter as ‘boy’. A deathly silence followed this faux pas.
Longman Language Activatormistake► mistake something incorrect that you do, say, or write without intending to: · Your essay is full of mistakes.· Celia corrected the mistakes with a pen.mistake in: · a tiny mistake in their calculationsmake a mistake: · Sampras was playing badly, making a lot of mistakes.there's a mistake: · There must be some mistake - I definitely paid the bill last week.
► error a mistake - use this especially to talk about mistakes in calculating or in using a language, system, or computer: · An error occurred in the processing of your application.error in: · There seems to be an error in the data.human error (=when a mistake is caused by people, not by a machine): · The report concluded that the accident was caused by human error.computer error (=a mistake caused by a computer): · Over 50 people were denied a vote through a computer error.
► slip a small unimportant mistake that is easy to make: make a slip: · Don't worry -- we all make slips from time to time.· People doing this kind of precision work can't afford to make the slightest slip.
► slip-up a careless mistake that may spoil a plan or process: · This whole situation only happened because of a slip-up by the bank.· If we are going to win the contract, we can't afford any more slip-ups.
► mix-up a careless mistake that causes confusion about details, for example someone's name, the time of a meeting etc: · The police have now returned Mr Sullivan's car and apologized for the mix-up.mix-up over: · There was a mix-up over the train times and I arrived two hours late.mix-up in: · I'm afraid there's been a mix-up in the booking - we were expecting you tomorrow.
► oversight a mistake that you make by not noticing something or by forgetting to do something: · I'm sure it was just an oversight that your name wasn't on the list.· The bank apologized for the oversight.· Due to an administrative oversight, several members of staff did not receive pay checks this month.
► slip of the tongue when you accidentally say a different word from the word you intended to say, sometimes with embarrassing results: · He quickly corrected his unfortunate slip of the tongue.· Did I say "Harlow"? Sorry, I meant "Harrow". It was just a slip of the tongue.
► boob British /booboo American informal a silly mistake, especially one that amuses people: · We labelled the pictures with the wrong names, but the boob was spotted by one of our readers.make a boob/booboo: · Whoops! I think I've made a booboo.
► howler a very bad mistake, especially one that shows you do not know something: · He read out a selection of howlers from students' exam answers.
We cannot afford another slip-up.► see thesaurus at mistake