# deadliest

/ˈdɛdɫiəst/ (US) · /dˈɛdliəst/ (UK) · CEFR B2 · Adjective

Source: https://englishreference.com/word/deadliest
Updated: 2026-05-06

## Definition

describes something that is the most likely to cause death or is the most dangerous.

For teachers: the superlative form of 'deadly'; refers to the entity or event that causes the greatest number of fatalities or possesses the highest potential for lethal outcomes.

## Examples

- The cobra is one of the deadliest snakes in the world.
- The 1918 flu pandemic remains one of the deadliest health crises in modern history, claiming millions of lives worldwide.
- While many predators rely on sheer strength, the deadliest species often utilize specialized toxins or camouflage to ensure their hunts are successful with minimal energy expenditure.

## Pitfalls

- Not "the most deadliest" but "the deadliest" — Deadliest is already a superlative; adding 'most' creates a double superlative error.

## Usage notes

- Superlative form; typically precedes the noun it modifies or follows a linking verb.

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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.