# ensure

/ɛnˈʃʊɹ/ (US) · /ɛnʃˈɔː/ (UK)

Source: https://englishreference.com/word/ensure
Updated: 2026-06-19

## Senses

### 1. to make certain

verb · CEFR B2 · Academic

to make sure that something happens or is true.

For teachers: to make certain that a specific outcome, condition, or event occurs. Transitive — typically followed by a 'that' clause or a noun phrase.

- Please ensure that all the windows are closed before you leave the house.
- The new safety protocols were designed to ensure that no unauthorised personnel could access the laboratory after hours.

Usage: Commonly followed by a 'that' clause; in informal contexts, 'that' is often omitted.

Teaching tip: Learners often confuse 'ensure' with 'insure' (related to money/insurance) or 'assure' (to tell someone something to remove their doubt).

## Examples

- Please ensure that all the windows are closed before you leave.
- The new safety regulations are designed to ensure the protection of every worker on the site.
- To ensure the longevity of the historical documents, the museum maintains a strictly controlled environment with specific levels of humidity and light.

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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.