ENGLISH
REFERENCE

lethal

adj.
C1 Advanced Oxford US //ˈɫiθəɫ// UK //lˈiːθəl// lethal

adj. strong enough to cause death. You use this to describe things like poisons, weapons, or dangerous situations that can kill people.

adj. sufficient to cause death. Often used in medical, forensic, or military contexts to describe substances, weapons, or dosages that result in a fatality.


SIMPLE

The snake's bite contains a lethal dose of venom.

CONTEXTUAL

The factory was evacuated immediately after a lethal gas leak was detected in the main laboratory.

COMPLEX

While the individual chemicals are relatively harmless, their combination creates a lethal reaction that requires specialized containment protocols to ensure the safety of the research staff.

Synonyms
Etymology 1

Learned borrowing from Latin lētālis (“deadly, mortal, fatal”), improperly written lēthālis, from lētum (“death”), improperly written as lēthum, from a supposed connection with Ancient Greek λήθη (lḗthē, “oblivion, forgetfulness”).

Etymology 2

Abbreviation of “lauric acid ethereal salt”, so called because it occurs in the ethereal salt of lauric acid.

Usage

Typically used to modify nouns like 'dose', 'weapon', 'injection', or 'combination'.

Pitfall

a lethal persona deadly personLethal usually describes objects, substances, or actions that cause death; 'deadly' is more common when describing a person's character or skills.

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