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hypothesis

n.
US //haɪˈpɑθəsəs// UK //haɪpˈɒθəsˌɪs// hy·poth·e·sis
  1. 1 scientific theory (n.)
    B2 Upper Intermediate Academic Science

    an idea that explains how something works, which scientists test with experiments to see if it is correct.

    a tentative conjecture explaining an observation or scientific problem that can be tested through investigation or experimentation.

    Example

    The researchers developed a hypothesis to explain why the plants were dying.

    Example

    The team formulated a hypothesis regarding the chemical composition of the soil, which they then tested through a series of controlled laboratory experiments.

    Usage

    Often used with the verbs 'formulate', 'test', 'confirm', or 'reject'.
  2. 2 an assumption (n.)
    C1 Advanced Academic Formal

    something that you assume is true so that you can start a discussion or an investigation.

    a premise or assumption taken to be true for the purpose of argument or investigation.

    Example

    Let us work on the hypothesis that the economy will improve next year.

    Example

    The entire legal argument was built upon the hypothesis that the defendant had no prior knowledge of the contract's specific clauses.

    Teacher's tip

    In everyday conversation, people often use 'theory' where 'hypothesis' would be more technically accurate.
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  1. 3 logic/math (n.)
    C2 Proficiency Technical Academic Math

    the first part of a logical statement, often starting with the word 'if'.

    the antecedent of a conditional statement; the 'if' clause in a logical implication.

    Example

    In the sentence 'If it rains, the ground gets wet', the hypothesis is 'it rains'.

    Example

    The mathematician demonstrated that if the initial hypothesis is false, the resulting theorem cannot be applied to this specific set of integers.
Origin

Recorded since 1596, from Middle French hypothese, from Late Latin hypothesis, from Ancient Greek ὑπόθεσις (hupóthesis, “base, basis of an argument, supposition”, literally “a placing under”), itself from ὑποτίθημι (hupotíthēmi, “I set before, suggest”), from ὑπό (hupó, “below”) + τίθημι (títhēmi, “I put, place”). Compare hypothec.

Word family

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