# rigor

/ˈɹɪɡɝ/ (US) · /ɹˈɪɡɐ/ (UK)

Source: https://englishreference.com/word/rigor
Updated: 2026-08-27

## Senses

### 1. strictness or precision

noun · CEFR B2 · American English

the quality of being very careful, thorough, and exact.

For teachers: the quality of being extremely thorough, exhaustive, or accurate. Often used in academic or professional contexts to describe high standards.

- The university is known for the academic rigor of its science programs.
- The study was criticized for lacking the statistical rigor necessary to support such a controversial conclusion.

Usage: Uncountable in this sense.

Teaching tip: Remind students that this is the American spelling; British English uses 'rigour'.

### 2. harsh conditions

noun · CEFR C1 · American English · Formal

the difficult or unpleasant conditions of something.

For teachers: the harsh, demanding, or unpleasant conditions of a particular environment or lifestyle.

- The soldiers were trained to survive the rigors of the desert.
- Few explorers were prepared for the physical rigors of the expedition across the frozen tundra.

Usage: Usually used in the plural form: 'the rigors of'.

### 3. medical chill

noun · CEFR C2 · Technical

a sudden feeling of cold with shivering and a high temperature.

For teachers: a sudden attack of shivering and a feeling of coldness, typically accompanied by a rapid rise in body temperature.

- The patient suffered a severe rigor shortly after the surgery.
- The onset of a high fever was preceded by a violent rigor that lasted for nearly twenty minutes.

Usage: Countable in medical reports.

## Examples

- The professor demands academic rigor in every essay.
- The new drug passed every safety test with the level of scientific rigor required by international law.
- While the initial hypothesis was bold, it lacked the analytical rigor necessary to survive a peer-review process conducted by the field's leading experts.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.