1 B1 idiomatic informal
To make a small or careless mistake
"The accountant slipped up and forgot to include the sales tax in the report."
inseparable
slip up
B1 informal inseparable intransitive
To make a small, careless mistake
In plain English
To make a small mistake, usually by not being careful enough
What does "slip up" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B1 idiomatic informal
To reveal something accidentally through a careless comment or action
"He slipped up and mentioned the surprise party in front of her."
inseparable
Literal vs figurative
Words literally mean
To lose one's footing and fall upward — not meaningful literally; wholly idiomatic
Actually means
To make a small mistake, usually by not being careful enough
Usage tip
The related noun 'a slip-up' (written with a hyphen) is very common. This phrasal verb implies the mistake was avoidable and usually minor. Widely used in both British and American English.
Words that pair with "slip up"
Natural word combinations native speakers use most often.
mistake error once badly slightly again
How to conjugate "slip up"
The five tense forms you'll use most often.
Base
slip up
I/you/we/they
3rd person
slips up
he/she/it
Past simple
sliped up
yesterday
Past participle
sliped up
have + pp
-ing form
sliping up
continuous
Hear "slip up" in the wild
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