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REFERENCE

rigorous

adj.
US //ˈɹɪɡɝəs// UK //ɹˈɪɡəɹəs// rig·or·ous
  1. 1 thorough and careful (adj.)
    B2 Upper Intermediate Academic

    very careful and detailed to make sure everything is correct.

    characterised by scrupulous accuracy and attention to detail; adhering strictly to a set of standards or methods.

    Example

    The scientists conducted a rigorous test to make sure the new medicine was safe.

    Example

    The peer-review process for the journal is exceptionally rigorous, ensuring that only the most methodologically sound research reaches publication.

    Usage

    Often used to describe research, testing, analysis, or training.
  2. 2 strict and demanding (adj.)
    B2 Upper Intermediate

    strict and following the rules exactly, often in a way that is difficult.

    strictly applied or enforced; demanding high levels of discipline or effort.

    Example

    The army has a rigorous training program for new soldiers.

    Example

    The academy maintains rigorous standards of conduct, and students who fail to comply are often asked to leave.
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  1. 3 harsh or severe (adj.)
    C1 Advanced Literary

    very difficult or unpleasant to live through, like a cold winter.

    harsh, severe, or extremely inclement, particularly in reference to weather or living conditions.

    Example

    The explorers had to survive a rigorous winter in the mountains.

    Example

    The expedition was ill-prepared for such a rigorous climate, lacking the specialised equipment necessary to endure sub-zero temperatures for months.
Origin

Inherited from Middle English rigorous, from Middle French and Anglo-Norman rigoreus, derived from Late Latin rigōrōsus (stiff, rigid; inflexible). By surface analysis, rigor + -ous.

Word family

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