Verb B1 — Intermediate /rɪˈdjuːs/

Reduce — Definition, Examples & Usage

To make something smaller, less, or simpler — an essential verb for academic and everyday English.

Quick Definition

To reduce means to make something smaller or less in size, amount, or degree; to bring something to a lower or simpler state. Regular revision helps reduce the time needed to memorise new vocabulary.

What Does Reduce Mean?

Reduce comes from the Latin reducere — formed from re- (back) and ducere (to lead). The original Latin sense was "to lead back" or "to restore to a previous state". By the 16th century, English had developed the sense of "making smaller or lesser" that dominates today.

In modern British English, reduce is a highly productive verb used across every register. In everyday speech you might reduce the volume or reduce your spending. In academic writing, phrases such as significantly reduce emissions or help to reduce inequality are extremely common. In cooking, to reduce a sauce means to simmer it until it thickens and decreases in volume. In mathematics, to reduce a fraction means to simplify it to its lowest terms.

Note that reduce usually implies deliberate, controlled action by an agent — compare with decrease, which can describe an automatic or unplanned fall in a measurement. Also note the fixed phrase reduced to + noun or gerund, which describes being brought to a worse or simpler condition: reduced to tears, reduced to begging.

Example Sentences

SentenceLevel & usage note
Please reduce the noise — the baby is sleeping. A2 — direct imperative, everyday context
The shop has reduced its prices by twenty per cent this week. B1 — present perfect, transitive with object + by-phrase
Regular revision helps reduce the time needed to memorise new vocabulary. B1 — study context, reduce + noun phrase
The new policy aims to reduce carbon emissions by at least thirty per cent before 2035. B2 — aim to + reduce, formal/environmental register
Prolonged economic hardship had reduced the once-thriving community to near destitution. C1 — reduced to + noun, formal written register, nuanced sense of deterioration

Collocations

CollocationExample
reduce costsThe company is looking for ways to reduce costs without cutting jobs.
reduce stressRegular exercise is one of the best ways to reduce stress.
reduce the riskWearing a seatbelt significantly reduces the risk of serious injury.
reduce emissionsWe must act now to reduce greenhouse gas emissions.
reduce speedDrivers are asked to reduce speed when approaching the school.
reduce wasteBuying loose fruit and vegetables helps reduce plastic waste.
reduce the gapBetter education can help reduce the gap between rich and poor.
reduce inflationThe central bank raised interest rates to reduce inflation.
significantly reduceThe new treatment has significantly reduced the number of relapses.
reduce toThe intense heat reduced the wooden structure to ashes within minutes.

Usage Notes

How to use reduce correctly

Transitive verb: Reduce nearly always takes a direct object. Do not say "prices reduced" when you mean someone actively lowered prices — say "the shop reduced its prices" or "prices were reduced" (passive).

Reduce by vs. reduce to: Use reduce by to show the amount of change — "reduced by 20%". Use reduce to to show the final value or state — "reduced to £50", "reduced to rubble".

Register: Reduce is neutral and fits all registers, from informal speech to academic writing. In very informal British speech, cut or bring down are common informal alternatives: "They've cut the price" or "We need to bring costs down."

Cooking use: In British recipes, "reduce the sauce" or "reduce by half" are standard instructions meaning to boil a liquid until its volume decreases and flavour concentrates.

Common Mistakes

Watch Out For

The government want to reduce the pollution. (missing article with countable modified noun)

The government wants to reduce pollution. (uncountable noun, no article needed here)

We reduced our prices with 10%. (incorrect preposition)

We reduced our prices by 10%. (use by to indicate the margin of change)

Sales have been reducing since last year. (reduce is rarely used in continuous aspect)

Sales have been falling / have reduced since last year. (use fall or simple perfect for gradual change)

Word Family

reduction (noun) reduced (adjective) reductive (adjective) reducer (noun) irreducible (adjective)

Synonyms

decrease lower cut diminish lessen minimise curtail trim

Antonyms

increase raise expand enlarge amplify

Related Vocabulary

increase improve limit change control All Common Words → Grammar Glossary

Practise This Word

Flash Cards Complete the Sentence Vocabulary Quiz Hangman

Frequently Asked Questions about “reduce”

What does reduce mean in English?
Reduce means to make something smaller, fewer, or less in size, quantity, degree, or intensity. It can also mean to bring something to a lower or simpler state — for example, 'reduce a sauce' in cooking or 'reduce a fraction' in mathematics. It is a B1-level verb used across everyday, academic, and professional English.
What is the difference between reduce and decrease?
Both reduce and decrease mean to make something smaller or lower. Reduce is more versatile — it collocates with a wide variety of nouns (reduce costs, reduce stress, reduce speed) and often implies deliberate action. Decrease is slightly more formal and is frequently used to describe measurements or statistics falling over time, sometimes without a specific agent causing the change.
What is the noun form of reduce?
The main noun form is reduction: 'a reduction in price', 'a significant reduction in crime'. The adjective forms are reduced ('a reduced rate') and reductive ('a reductive argument'). The adverb reducibly is rare in everyday use.
How do you use reduce in a sentence?
Reduce is a transitive verb and normally takes a direct object: 'We need to reduce our carbon footprint.' It is often followed by a prepositional phrase showing the extent or target: 'reduce costs by 20%', 'reduce the temperature to 180°C'. Avoid using reduce without an object in formal writing.
What are common collocations with reduce?
Common collocations include: reduce costs, reduce stress, reduce the risk, reduce emissions, reduce speed, reduce waste, reduce the gap, reduce inflation, reduce a sentence (legal), and reduce to ashes. In academic writing, 'significantly reduce' and 'help to reduce' are especially frequent.
What is the opposite of reduce?
The most common antonyms of reduce are increase and raise. Expand, enlarge, and grow can also function as opposites depending on the context. In the sense of simplifying, the opposite might be complicate or elaborate.
Is reduce followed by a gerund or an infinitive?
Reduce is not directly followed by a gerund or infinitive to describe the action itself — it takes a noun object: 'reduce stress', 'reduce costs'. However, you may see structures like 'help to reduce' or 'aim to reduce' where the infinitive belongs to a preceding verb, not to reduce itself.
What is the etymology of reduce?
Reduce comes from Latin reducere, meaning 'to lead back' or 'to bring back', formed from re- (back) and ducere (to lead). It entered English in the late 14th century via Old French. The original sense was 'to restore' or 'to bring back to a previous state'; the modern sense of 'making smaller' developed by the 16th century.
Can reduce be used in a passive voice?
Yes. Passive constructions are very common with reduce: 'The price was reduced by 30%.' 'Pollution levels have been significantly reduced since 2010.' 'The sentence was reduced on appeal.' Passive voice with reduce appears frequently in academic, journalistic, and legal writing.
How can I practise the word reduce?
Use LexFizz's Complete the Sentence exercise to see reduce used in authentic contexts, or try Flash Cards to test the full word family (reduce, reduction, reduced, reductive). Writing sentences using the collocations 'reduce costs', 'reduce stress', and 'reduce the risk' is a highly effective way to make the word part of your active vocabulary.