keep out
stop someone or something from going into a place
What does "keep sb/sth out" mean?
Examples
- We put up a fence to keep out the deer.
- The thick curtains keep the noise out surprisingly well.
- Security guards were stationed at the door to keep out anyone without a pass.
How to use it
The most common pattern, used when the object is a noun phrase. The particle stays directly after 'out'.
We installed a new gate to keep out strangers.
Used when you want to separate the verb and particle, especially with short noun phrases. This is very natural and often preferred with short objects.
The thick walls keep the cold out during winter.
When the object is a pronoun, it must go between 'keep' and 'out' — it cannot go after 'out'.
There's a security code on the door to keep them out.
The passive form is natural when you want to focus on the person or thing being prevented from entering.
The reporters were kept out of the press conference.
Used as a fixed warning expression on signs or in speech, meaning 'Do not enter'.
There was a sign on the door that said 'Keep out!'
Common Collocations
Common Mistakes
When the object is a pronoun (them, him, her, it), it must go between 'keep' and 'out'. Putting it after 'out' is incorrect.
'Keep out' (transitive) means to prevent others from entering something. 'Keep out of' is often used to tell someone to stay away from a place or situation themselves. These look similar but have different meanings and structures.
'Lock out' specifically means to prevent entry using a lock or security mechanism. 'Keep out' is more general and covers any kind of barrier or preventive measure, so they are not always interchangeable.
Usage
This phrasal verb is neutral and works in both spoken and written English. The imperative 'Keep out!' is very common on warning signs and is a fixed, natural expression.
Frequently Asked Questions
Can 'keep out' be used for things like weather or noise, not just people?
Yes, absolutely. 'Keep out' is very commonly used for physical things like cold, rain, wind, noise, and insects — not just people. For example, 'These windows keep out the wind' or 'The earplugs kept out most of the noise' are both perfectly natural.
Can I use 'keep out' in a metaphorical way, like for business or competition?
Yes, you can extend the meaning beyond physical spaces. It is natural to say things like 'They tried to keep rival companies out of the market' or 'New rules were designed to keep outside investors out'. The idea of preventing entry or access works in these situations too.
Is 'Keep out!' on a sign correct English?
Yes, 'Keep out!' is a very common and natural fixed expression used on warning signs and notices. It is the standard way to say 'No entry' or 'Do not enter' in informal and everyday contexts, and learners do not need to change or rephrase it.
Does 'keep out' always need an object?
In most situations, 'keep out' is used with an object — something or someone is being kept out. However, in the imperative form 'Keep out!', no object is needed because the message is directed at the person reading or hearing it.
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