knock down

3 meanings

Meanings
  1. 1 destroy a building or part of a building B2
  2. 2 hit someone with a vehicle so they fall to the ground B2
  3. 3 lower the price of something B2
1 knock sth down

destroy a building or part of a building

B2

What does "knock down" mean in this sense?

To knock down a building means to deliberately demolish it — to destroy it completely so that it no longer stands. This is typically done as part of a planned project, using machinery such as a wrecking ball or excavator. The phrasal verb is strongly associated with urban development: old factories, tower blocks, or derelict warehouses are knocked down to make way for new housing, roads, or commercial buildings. It often appears in contexts where demolition is controversial — for example, when a historic building is knocked down despite local protests. While 'demolish' is the more formal single-word equivalent you'd find in planning documents, 'knock down' is the natural, everyday choice in speech and informal writing.

Examples

How to use it

knock down + building

The most common pattern: the building being demolished follows the particle directly.

The council plans to knock down the old warehouse on the high street.

knock + building + down

With short noun phrases, the object can sit between the verb and particle — both positions are natural.

They knocked the tower block down to make room for a new park.

knock + pronoun + down

When using a pronoun instead of a noun, it must go between the verb and particle — never after 'down'.

The building was unsafe, so the council decided to knock it down.

be knocked down

The passive is very natural and common, especially when the focus is on the building rather than who is doing the demolishing.

Several Victorian terraces were knocked down in the 1960s to make way for the new ring road.

be going to knock down + building

This future construction is frequently used when discussing plans or proposals for demolition.

They're going to knock down the old school and build a block of flats on the site.

Common Collocations

old buildingfactorywalltower blockterraced housesderelict site

Common Mistakes

Pronoun placement

When you replace the object with a pronoun like 'it' or 'them', it must go between 'knock' and 'down', never after 'down'.

The building was dangerous, so they knocked down it.
The building was dangerous, so they knocked it down.
Confusing the three senses of 'knock down'

'Knock down' has other meanings — it can mean to hit and floor someone, or to reduce a price. The demolition sense is only correct when the object is a building or structure, and the action is deliberate.

They knocked down the price of the old factory. (if you mean they demolished it)
They knocked down the old factory. (demolition) / They knocked down the price. (price reduction)
Awkward separation with long noun phrases

Separation works well with short objects or pronouns, but placing a very long noun phrase between 'knock' and 'down' sounds unnatural — it's better to keep the particle directly after 'down' in those cases.

They knocked the old Victorian factory at the end of the road down.
They knocked down the old Victorian factory at the end of the road.

Usage

'Knock down' is the natural, everyday way to talk about demolishing buildings in British English. Use 'demolish' in formal or technical writing (e.g. planning documents), but 'knock down' in speech and informal writing.

2 knock sb down

hit someone with a vehicle so they fall to the ground

B2

Sense 2: What does "knock sb down" mean?

When a vehicle such as a car, bus, or lorry hits a person with enough force to make them fall to the ground, you can say they were knocked down. The emphasis is on the collision and the impact that causes the person to fall — not on what happens afterwards. This phrasal verb appears very frequently in news reports, police statements, and everyday accounts of road accidents. It is particularly common in British English; in American English, people often prefer expressions like 'hit by a car' to describe the same event. Because the victim is usually the focus of the sentence, the passive form — 'was knocked down by a car' — is by far the most natural and common way to use this expression.

Examples

How to use it

be knocked down by + vehicle

The passive construction is the dominant pattern for this sense, since the focus is on the person who is hit rather than the driver or vehicle.

A jogger was knocked down by a van on the high street early this morning.

vehicle + knock down + person

In active constructions, the person (object) typically follows 'down' unless it is a pronoun.

A lorry knocked down the cyclist as she turned onto the main road.

vehicle + knock + pronoun + down

When the object is a pronoun, it must go between 'knock' and 'down'.

The car came out of nowhere and knocked him down before anyone could react.

nearly / almost + be knocked down

Adverbs like 'nearly' and 'almost' are very common with this phrasal verb, describing near-miss accidents.

She nearly knocked down a teenager who stepped into the road without looking.

knocked down and + past participle

This pattern is common in accident reporting, describing the result of the collision alongside the impact itself.

The report confirmed that the pedestrian had been knocked down and seriously injured near the junction.

Common Collocations

knocked down by a carknocked down by a lorry/truckknocked down crossing the roadknocked down and killednearly knocked downpedestrian knocked down

Common Mistakes

Confusing 'knock down' with 'run over'

'Knock down' focuses on the impact of a vehicle hitting someone and causing them to fall. 'Run over' means the vehicle actually drives over the person's body — a more serious and specific action. Using them interchangeably can be inaccurate.

He was run over by a bus, but luckily he wasn't seriously hurt and the vehicle didn't touch him.
He was knocked down by a bus, but luckily he wasn't seriously hurt.
Confusing senses of 'knock down'

'Knock down' has other unrelated meanings — including demolishing a building and reducing a price. Make sure the context makes it clear that a vehicle is hitting a person, otherwise readers may misunderstand which sense you mean.

They knocked down the wall in the accident report.
The pedestrian was knocked down in the accident and taken to hospital.
Using unnatural tenses

Because this phrasal verb typically describes a completed event, the present continuous and future simple sound awkward in most contexts. Stick to past tenses, the present perfect, or the passive for natural-sounding sentences.

A car will knock down someone on that road eventually — it is too dangerous.
A car has knocked down several people on that road — it is too dangerous.

Usage

The passive form ('was knocked down by a car') is by far the most common pattern in both spoken and written English, especially in news reports and accident descriptions. This phrasal verb is more common in British English; American speakers often say 'hit by a car' instead.

3 knock sth down

lower the price of something

B2

Sense 3: What does "knock sth down" mean?

To knock down a price means to reduce it, usually through negotiation or a direct request. It strongly suggests that someone — often a buyer — has asked for a lower price, or that a seller has agreed to accept less than the original amount. You might hear it at a market stall, a car dealership, or when discussing rent or service fees. Unlike a standard discount or sale price, knocking something down implies a personal, often one-off concession rather than a routine price cut. It is slightly more informal than 'reduce' or 'lower', but comfortable in both spoken and written contexts.

Examples

How to use it

knock + object + down

The most common separated form, used when the object is a noun such as a price, cost, or fee.

She managed to knock the asking price down by nearly €2,000.

knock + pronoun (it/them) + down

When the object is a pronoun, it must go between 'knock' and 'down' — this position is not optional.

The fee seemed high, so I asked if they could knock it down a bit.

knock down + noun object

The unseparated form is also possible with noun objects, though the separated form is often more natural.

The dealer agreed to knock down the price after we said we were paying in cash.

knock + object + down + to/from … to …

Use 'to' to state the new price, or 'from … to …' to show both the original and reduced amounts.

He knocked the rate down from £800 to £650 once we agreed to sign a longer contract.

be knocked down + to/from … to …

The passive is natural when the focus is on the price rather than the person doing the reducing, common in retail or negotiation write-ups.

The cost was knocked down to £180 after a short negotiation at the market.

Common Collocations

the pricethe costthe feethe ratethe asking priceit (pronoun)

Common Mistakes

Pronoun placement

When using a pronoun like 'it' or 'them', it must go between 'knock' and 'down'. Placing it after 'down' is ungrammatical in English.

Can you knock down it a little?
Can you knock it down a little?
Confusing 'knock down' with 'mark down'

'Mark down' refers to an official, often store-wide price reduction — like a sale label on a shelf. 'Knock down' implies informal bargaining or a personal concession between two people. They are not always interchangeable.

All the winter coats were knocked down by 30% in the January sale.
All the winter coats were marked down by 30% in the January sale.
Using a non-financial object

In this sense, the object must be a price, cost, fee, or similar financial term. Using a physical object as the object shifts the meaning to demolition or a physical collision, which are completely different senses.

They knocked down the old warehouse to lower costs.
They knocked down the quote significantly when we told them our budget.

Usage

This phrasal verb is neutral in register and works in both spoken and written English, but it feels most natural in personal negotiation contexts (markets, car sales, property). It is slightly more informal than 'reduce' or 'lower'.

Frequently Asked Questions

Can 'knock down' be used in the passive?

Yes, the passive is very natural and widely used with this sense. It's especially common in news articles and community discussions where the focus is on the building rather than who demolished it. For example: 'The old cinema was knocked down last year to make way for a supermarket.'

Is 'knock down' the same as 'tear down' or 'pull down'?

'Pull down' is a close synonym in British English with very little difference in meaning — the choice is mostly stylistic. 'Tear down' is more emphatic and more common in American English, though it's understood internationally. 'Knock down' is the most neutral and widely used option in everyday British English.

What kinds of things can be knocked down?

In this demolition sense, the object should always be a building or structure — for example, a factory, warehouse, tower block, wall, church, or terraced house. You can't use this sense with people or prices; those are completely different meanings of 'knock down'.

When should I use 'demolish' instead of 'knock down'?

'Demolish' is the more formal, technical equivalent and is preferred in official documents such as planning applications or legal notices. In conversation and informal writing, 'knock down' is the more natural and common choice. Both are correct and widely understood.

Does 'knock down' suggest the demolition was a bad thing?

Not necessarily — the phrasal verb itself is neutral. However, it often appears in contexts where demolition is controversial, such as when a historic or well-loved building is destroyed despite objections. Words like 'finally', 'despite protests', or 'plans to' often appear alongside it, giving the sentence a slightly charged tone depending on context.

Is 'knock down' more common in British or American English?

It is more common in British English, particularly in news reports and police statements. American English speakers tend to use phrases like 'hit by a car' or 'struck by a vehicle' in the same situations. However, American speakers will still understand 'knock down' in this sense.

Does 'knock down' always refer to a vehicle hitting someone?

No — 'knock down' has other meanings. It can mean to demolish a building, or to reduce a price. This road accident sense is specifically about a vehicle striking a person and causing them to fall. Context usually makes the meaning clear, especially when a vehicle is mentioned.

Why do I see 'was knocked down' so often in news articles?

Because the victim — the person who was hit — is usually the most important focus in accident reporting, the passive voice is the natural and dominant form for this phrasal verb. Phrases like 'was knocked down by a car' or 'was knocked down crossing the road' are standard in both journalism and police language.

If someone is knocked down, does it mean they lost consciousness?

Not necessarily. 'Knock down' means a vehicle hit someone and caused them to fall to the ground — it says nothing about whether they were rendered unconscious. If you want to say someone lost consciousness, you would use 'knock out' instead.

Can I use 'knock down' to describe an accident that happened in the past but I'm not sure exactly when?

Yes — the present perfect works well for this: 'A cyclist has been knocked down near the school.' This is common in news reports when the exact time is not the focus. For a specific past event with a known time, the simple past is more typical: 'She was knocked down last Thursday morning.'

Does 'knock down' always mean reducing a price, or does it have other meanings?

No — 'knock down' has several distinct meanings in English. This entry covers only the price-reduction sense. The other senses (such as demolishing a building or causing someone to fall) are completely separate and handled elsewhere on this platform.

Can I use 'knock down' when talking about a shop having a sale, or is it only for face-to-face negotiation?

It works best in personal negotiation contexts — markets, car sales, property deals, or service fees — where one person agrees to accept less. For official, store-wide reductions like sale events, 'mark down' is usually the more natural choice.

Can I say 'knock down the price by 20%' or does it only work with a specific amount?

Both work well. You can specify an exact amount ('knock the price down by £50'), a percentage ('knock it down by 20%'), or simply use a vague amount ('knock it down a bit'). You can also show the before-and-after with 'from … to …', for example 'knocked down from £400 to £300'.

Is it natural to say 'they are knocking the price down right now'?

This sounds a little unnatural in most situations. 'Knock down' in this sense usually describes a completed decision or a direct request, so the simple past or present perfect tends to sound more natural. The present continuous can work if you want to stress that a negotiation is actively happening at that moment, but it is not the default choice.

Who typically 'knocks down' a price — the buyer or the seller?

Either person can be the subject grammatically, but the action is usually something a seller does, often in response to pressure from a buyer. A buyer might ask 'Can you knock it down at all?' and the seller is the one who ultimately knocks the price down. You can also say a buyer 'knocked the price down' to mean they successfully negotiated a reduction.

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