Synonyms Word Origin See more synonyms on Thesaurus.com of, relating to, or causing death; deadly; fatal: a lethal weapon; a lethal dose. made or carried out to cause death: a lethal chamber; a lethal attack. causing great harm or destruction: The disclosures were lethal to his candidacy. Origin of lethal 1575–85;
) death +
-ālis -al 1
; spelling (hence pronunciation) with
by association with
Related forms le·thal·i·ty, le·thal·ness, noun le·thal·ly, adverb hy·per·le·thal, adjective non·le·thal, adjective non·le·thal·ly, adverb sem·i·le·thal, adjective
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for lethalness able to cause or causing death of or suggestive of death Derived Forms lethality ( liːˈθælɪtɪ), noun lethally, adverb Word Origin
C16: from Latin
lēthālis, from lētum death
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Word Origin and History for lethalness lethal adj.
1580s, from Late Latin
lethalis, alteration of Latin letalis "deadly, fatal," from letum "death," of uncertain origin. Form altered in Late Latin by association with lethe hydor "water of oblivion" in Hades in Greek mythology, from Greek lethe "forgetfulness."
Online Etymology Dictionary, © 2010 Douglas Harper
lethal (lē ′thəl) Capable of causing death. Of, relating to, or causing death.
The American Heritage® Stedman's Medical Dictionary
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