# cyanide

/ˈsaɪˌnaɪd/ (US) · /sˈaɪɐnˌaɪd/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/cyanide
Updated: 2026-05-07

## Definition

a very strong and dangerous poison that can kill quickly. It is often used in movies or books as a fast-acting chemical.

For teachers: a highly toxic chemical compound containing the cyano group, consisting of a carbon atom triple-bonded to a nitrogen atom. It acts as a potent respiratory inhibitor in living organisms.

## Examples

- The detective found traces of cyanide in the victim's tea.
- Industrial plants must follow strict safety protocols when handling cyanide to prevent accidental exposure or environmental contamination.
- While naturally occurring in trace amounts in certain fruit pits, concentrated cyanide is historically notorious for its use as a lethal agent due to its ability to rapidly halt cellular respiration.

## Usage notes

- Usually uncountable when referring to the chemical substance; can be countable when referring to specific chemical salts (e.g., 'alkali cyanides').

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