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reduce

v.
US //ɹəˈdus// UK //ɹɪdjˈuːs// re·duce
  1. 1 to make smaller (v.)
    A2 Elementary

    to make something smaller in size, amount, degree, or price.

    to diminish the size, quantity, value, or intensity of something. Transitive, requiring a direct object.

    Example

    The shop decided to reduce the price of the coats to sell them faster.

    Example

    The government implemented new policies to reduce carbon emissions by thirty percent over the next decade.

    Usage

    Often used with 'by' for amounts or 'to' for a final result.
  2. 2 to be forced into a state (v.)
    B2 Upper Intermediate

    to be forced into a worse or simpler situation.

    to bring someone or something to a lower or more desperate state or condition. Often used in the passive voice.

    Example

    After the fire, the family was reduced to living in a small tent.

    Example

    The once-mighty empire was reduced to a handful of small islands after the long and costly war.
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  1. 3 cooking (v.)
    B2 Upper Intermediate Cooking

    to boil a liquid so that some of it disappears and the rest becomes thicker.

    to decrease the volume of a liquid by boiling, thereby concentrating its flavour and increasing its viscosity.

    Example

    You should reduce the sauce for ten minutes to make it more flavourful.

    Example

    The chef instructed the apprentice to reduce the balsamic vinegar until it reached a syrupy consistency suitable for glazing the duck.
  2. 4 chemistry (v.)
    C1 Advanced Technical Science

    to add electrons to a substance or remove oxygen from it.

    to cause a substance to gain electrons or lose oxygen during a chemical reaction.

    Example

    In this reaction, the iron oxide is reduced to pure iron.

    Example

    The process involves reducing the metal ore in a blast furnace to extract the pure element from its oxide form.
    • oxidize
  3. 5 mathematics (v.)
    B2 Upper Intermediate Academic Math

    to change a fraction or equation into a simpler form.

    to simplify a mathematical expression or fraction by removing common factors without changing its value.

    Example

    The teacher asked the students to reduce the fraction to its simplest form.

    Example

    Before solving for the variable, you must reduce the equation by dividing both sides by the common denominator.
  4. 6 medicine (v.)
    C2 Proficiency Technical Medicine

    to put a broken bone or a joint back into its correct place.

    to restore a fracture or dislocation to its correct anatomical alignment through manual or surgical intervention.

    Example

    The doctor had to reduce the patient's dislocated shoulder in the emergency room.

    Example

    The surgeon successfully reduced the compound fracture, ensuring the bone fragments were perfectly aligned before applying the internal fixation.
Origin

From Middle English reducen, from Old French reduire, from Latin redūcō (“reduce”); from re- (“back”) + dūcō (“lead”). See duke, and compare with redoubt.

Idioms1 entry

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