reduction

reduction — noun

1. the process or result of making something take up less space, cost less money, n

1.nounB2
Definition

the process or result of making something take up less space, cost less money, need fewer resources, or be less important than before.

Example

The company announced a 15% reduction in its workforce after a difficult year.

reduction in + noun phrase

Residents welcomed the reduction of traffic noise after the new bypass opened.

reduction of + noun phrase

Synonyms
  • decrease

    the closest synonym; used for numbers, statistics, and measurable quantities

  • cut

    suggests a deliberate, often planned reduction, especially in spending or staff

  • decline

    implies a gradual, continuous downward movement, often over time

  • drop

    suggests a sudden or sharp fall in amount or level

Antonyms
  • increase

    used when amount, size, or level becomes larger

  • rise

    suggests an upward movement, often gradual

  • growth

    suggests a steady expansion in size or importance

Grammar Patterns

reduction in + noun phrase

reduction of + noun phrase

reduction by + percentage/number

Usage Note

Can be countable or uncountable. When talking about the general process, use uncountable (e.g. 'Reduction of waste is important'). When talking about a specific instance or published figure, use countable (e.g. 'a 10% reduction in costs').

Common Mistakes

There was a reduction of price 10%.
There was a 10% reduction in price.
'reduction in' is the standard pattern for percentages and quantities.
We need to do a reduction of the budget.
We need to make a reduction to the budget.' or 'We need to reduce the budget.
'make' is the natural verb partner, and the verb 'reduce' is often simpler.
The reduction of the problem took two hours.' (when meaning solving)
The solution of the problem took two hours.
'reduction' does not mean solving a problem or fixing an issue.

2. a smaller version of an image, such as a photograph, drawing, or document, creat

2.nounB2
Definition

a smaller version of an image, such as a photograph, drawing, or document, created by making the original smaller.

Example

Tomás bought a reduction of the museum's most famous painting as a souvenir.

reduction of [artwork] as [purpose]

The wedding album contained a reduction of every group photo on a single page.

Synonyms
  • miniature

    usually a very small model or copy, especially of a three-dimensional object

  • thumbnail

    a very small version of an image, especially used in digital contexts

Antonyms
  • enlargement

    a copy that is made bigger than the original, especially of a photograph

Grammar Patterns

reduction of + artwork/document

3. in chemistry, a process in which a chemical substance picks up electrons from an

3.nounC1
Definition

in chemistry, a process in which a chemical substance picks up electrons from another substance during a reaction, changing its electrical charge.

Example

In the lab, reduction occurs when a metal ion gains electrons from another substance.

reduction occurs when + electrons gained

During reduction, the copper ions in the solution changed into solid copper metal.

Antonyms
  • oxidation

    the opposite process in which electrons are lost

Grammar Patterns

reduction of + substance

reduction occurs when/if

Usage Note

In chemistry, reduction always happens together with its opposite, oxidation. The phrase 'redox reaction' combines both processes.

Common Mistakes

Reduction means losing electrons.
Reduction means gaining electrons.
This is a common confusion; think of 'reduction of charge' (the charge number is reduced/gains electrons).

4. a medical procedure in which a doctor returns a fractured bone or displaced join

4.nounC1
Definition

a medical procedure in which a doctor returns a fractured bone or displaced joint to its natural position.

Example

After examining the X-ray, Dr. Lakan performed a closed reduction of the wrist fracture.

closed reduction of [body part] fracture

The patient needed surgery because a simple reduction of the dislocated shoulder was not enough.

Grammar Patterns

reduction of + body part

closed reduction

open reduction

Usage Note

In medical contexts, 'closed reduction' means the bone is moved back into place without cutting the skin. 'Open reduction' involves surgery to reach the bones directly.

Word family

  • reduce
    verbB1
  • reduced
    adjectiveB2
  • reductive
    adjectiveC1
  • reductionist
    adjectiveC2
  • reducibility
    nounC2

Synonym discussion

Sense: noun/1

Reduction is a general term for making something smaller in size, amount, or degree. Decrease is the closest synonym and is interchangeable in most contexts involving numbers and statistics ('a decrease in temperature'). Decline suggests a gradual, continuous downward movement, often in quality or quantity over time ('a decline in manufacturing output'). Cut refers to a deliberate, often planned reduction, especially in budgets, spending, or workforce ('a cut in education funding'). Drop implies a sudden or significant fall in level or amount ('a drop in sales this quarter'). Use reduction for neutral, general contexts; choose cut for intentional actions; prefer decline for gradual trends; and use drop for sharp changes.

decrease ↗decline ↗cut ↗drop ↗

Common collocations

Nouns

Adverbs

Phrases

  • reduction in force
  • reduction to the bone

Prepositions

Etymology

LatinMiddle FrenchEnglish

The word 'reduction' comes from Latin 'reductio', meaning 'a leading back or bringing back'. It is formed from 're-' (back) and 'ducere' (to lead). The term entered English through Middle French 'reduction' in the 15th century. The original sense of 'bringing back' faded, and by the 1600s the word was used mainly for 'making smaller'. The chemistry meaning (gain of electrons) developed in the late 1700s, and the medical meaning (bone setting) dates from the same period.