English Reference
noun

deduction

n.
US /dɪˈdəkʃən/ UK /dɪdˈʌkʃən/ de·duc·tion UK spelling deduction's, deduction's

  1. 01 B2 Upper Intermediate Finance

    an amount of money that is taken away from a total, such as taxes taken from your pay.

    the subtraction of an amount from a gross total; frequently used in taxation and payroll contexts to describe non-taxable expenses or mandatory withholdings.

    Simple

    After the tax deduction, my take-home pay was lower than I expected.

    In context

    The accountant identified several legitimate business deductions that significantly reduced the company's overall tax liability for the fiscal year.

  2. 02 B2 Upper Intermediate

    the process of reaching a decision or answer by thinking about the facts you know.

    the logical process of reaching a specific conclusion from general premises or known facts; the conclusion must be true if the premises are true.

    Simple

    Through a process of deduction, the detective identified the thief.

    In context

    The scientist used logical deduction to predict the outcome of the experiment based on established physical laws.

  3. 03 C1 Advanced Academic

    the specific conclusion or answer you find after thinking about the facts.

    the specific conclusion arrived at through the process of deductive reasoning.

    Simple

    His deduction that the water was poisoned turned out to be correct.

    In context

    The researcher's primary deduction was that the two variables were linked by a third, previously unobserved factor.

However, the club have had a six-point deduction, which was suspended until 30 June 2027, "set aside" on appeal.

BBC News· 18 Aug 2026

From Middle French déduction, from Latin deductio. Equivalent to deduct + -ion or deduce + -tion.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level B2 · Upper Intermediate
Frequency Frequent
Updated