mess up
2 meanings
spoil or ruin something
What does "mess up" mean in this sense?
Examples
- I completely messed up the job interview — I forgot the name of the company.
- Please don't mess things up this time; we only get one chance.
- The whole presentation was messed up because someone deleted the wrong file.
How to use it
The most common pattern — use it when naming the thing that was ruined or the mistake that was made.
She messed up the job interview by arriving half an hour late.
When the object is a pronoun (it, them, everything, things), it must go between 'mess' and 'up' — never after 'up'.
I had one chance to make a good impression and I messed it up.
Longer noun phrases can also go between 'mess' and 'up', especially in informal speech for emphasis.
He messed the whole deal up by sending the wrong figures to the client.
Used without an object to simply admit or describe making a mistake, without saying exactly what went wrong.
I completely messed up — I should have checked the deadline before sending it.
The passive form is natural and often used to describe a bad outcome without blaming one specific person.
The launch got messed up because the team didn't communicate properly.
Common Collocations
Common Mistakes
When the object is a pronoun like 'it' or 'them', it must go between 'mess' and 'up'. Putting the pronoun after 'up' is ungrammatical in English.
'Mess up' refers to a specific mistake or ruined outcome, while 'mess around' describes wasting time or behaving irresponsibly without necessarily pointing to one bad result. They are not interchangeable.
'Mess up' is an informal, colloquial expression. In formal emails, reports, or academic writing, use alternatives like 'make a serious error', 'fail to meet expectations', or 'jeopardise the outcome'.
Usage
This phrasal verb is informal — use it in conversation and casual writing, but not in formal emails or academic work. It works equally in British and American English.
make something dirty or untidy
Sense 2: What does "mess sth up" mean?
Examples
- Don't mess up the kitchen — I just cleaned it.
- The kids completely messed the living room up while I was out.
- My hair was fine this morning, but the wind has messed it up.
How to use it
The most common pattern, where the object is a physical space or thing such as a room, floor, or surface.
Please don't mess up the kitchen — we have guests coming later.
With short noun phrases, separating the verb and particle is preferred and sounds more natural.
The dog messed the whole living room up while we were at work.
When the object is a pronoun, separation is always required — the pronoun must go between the verb and the particle.
I spent twenty minutes doing my hair, and the rain completely messed it up.
The passive form is natural when describing a space or object that has been left in a dirty or untidy state.
The spare room was completely messed up after the party.
The imperative form is very common, often used to warn someone not to make a tidy space untidy.
Don't mess up the bathroom — I just cleaned it.
Common Collocations
Common Mistakes
When you use a pronoun like 'it' or 'them', it must go between 'mess' and 'up'. Putting the pronoun after 'up' is incorrect.
This sense of 'mess up' is only used with physical things like rooms, hair, or furniture. If the object is something abstract like a plan or an opportunity, that is a different sense of the phrasal verb.
Usage
This phrasal verb is informal and suits everyday speech or casual writing. It is very common in imperatives and is used the same way in both British and American English.
Frequently Asked Questions
Can 'mess up' mean two different things?
Yes — 'mess up' has a second meaning: to make something physically untidy or dirty (for example, 'the kids messed up the living room'). The sense on this page is about ruining something or making a serious mistake. Context usually makes it clear which meaning is intended.
What does 'messed up' mean when it's used as an adjective?
When used as an adjective, 'messed up' describes either a situation that has gone badly wrong or a person who is in a troubled emotional state — for example, 'The whole situation is messed up' or 'He was completely messed up after losing the contract.' This adjectival use is very common in both British and American English.
Can I say 'I've been messing up the presentation'?
This sounds unnatural. 'Mess up' typically describes a single completed mistake or event, not a continuous ongoing action, so tenses like the present perfect continuous don't fit well. It's more natural to say 'I messed up the presentation' or 'I've messed up the presentation'.
What words can I use to make 'mess up' sound stronger?
You can add adverbs like 'completely', 'totally', 'really', or 'badly' before or after the verb — for example, 'I totally messed up' or 'she messed up badly'. In very informal speech, 'big time' and 'royally' are also used for emphasis: 'We messed up big time.'
Is 'mess up' used in both British and American English?
Yes, it is common and natural in both British and American English. There is no significant difference in meaning or usage between the two varieties for this phrasal verb.
What kinds of things can be the object of 'mess up' in this meaning?
The object should always be something physical and concrete — a room, a surface, a piece of furniture, or something like hair or clothing. Common examples include 'the kitchen', 'the carpet', 'my hair', and 'the bed'. If the object is something you can't physically touch, like a plan or a friendship, that belongs to a different meaning of 'mess up'.
Can I say 'I've been messing up the kitchen'?
This form sounds forced and unnatural for this meaning. It is more natural to use the simple past ('I messed up the kitchen') or the present perfect ('I've messed up the kitchen'). The present perfect continuous doesn't work well here.
Is 'mess up' used the same way in British and American English?
Yes — this phrasal verb is common and natural in both British and American English. You don't need to worry about regional differences with this one.
Can I add a word like 'completely' or 'really' for emphasis?
Yes, and it's very natural to do so. Adverbs like 'completely', 'really', or 'totally' often go before the object — for example, 'He completely messed up the bathroom' or 'She really messed the place up'. This makes the sentence sound more emphatic and is common in everyday speech.
Is 'mess up' okay to use in formal writing?
No — this phrasal verb is informal and suits everyday conversation or casual writing like texts and social media. In a formal context, such as an email to a landlord or a written report, you would use something like 'left in a very untidy state' instead.
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