lethal
Americanadjective
-
able to cause or causing death
-
of or suggestive of death
Related Words
See fatal.
Other Word Forms
Etymology
Origin of lethal
First recorded in 1575–85; from Latin lētālis, equivalent to lēt(um) “death” + -ālis -al 1; spelling (hence pronunciation) with -h- by association with Greek lḗthē “oblivion”; see Lethe ( def. )
Explanation
Lethal refers to anything dangerous enough to cause death. The cobra's venom is so lethal that if you get bitten and can't find the antidote, it's lights out forever. Poisonous spiders, guns, knives, and radiation — all of these things can be lethal because they have the ability to kill. Even some substances that on their own aren't dangerous can become lethal in large quantities. Eating a peanut butter sandwich won't hurt most people, but it can be lethal to those with a nut allergy. Words like deadly and fatal have meanings that are similar to lethal.
Vocabulary lists containing lethal
100 SAT Words Beginning with "J," "K," and "L"
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A Long Way Gone
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Silent Spring
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The rock-rap band, made up of Fred Durst, John Otto, DJ Lethal, and Rivers, formed in 1994 and was credited with helping to bring heavy music to the mainstream.
From BBC • Oct. 18, 2025
In a comment on the post, Leor Dimant — also known as DJ Lethal — asked people to “please respect the family’s privacy at this moment.”
From Los Angeles Times • Oct. 18, 2025
Appeared in the October 3, 2025, print edition as '‘Punch’: A Lethal Blow, a Life Reborn'.
From The Wall Street Journal • Oct. 2, 2025
Lethal means counseling is a way to make the worst outcomes less likely.
From Salon • May 28, 2024
Even on Earth, the skin of a Colombian golden poison frog had a waaaaay lower LD50—the Lethal Dose needed to kill 50% of a test population.
From "The Last Cuentista" by Donna Barba Higuera
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
