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definitions

lethal

[ lee-thuh l ]
/ ˈli θəl /
||
SEE MORE SYNONYMS FOR lethal ON THESAURUS.COM

adjective

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.

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RELATED WORDS

mortal, destructive, murderous, noxious, dangerous, poisonous, devastating, pernicious, harmful, malignant, virulent, fatal, baleful, deathly, hurtful, mortuary, pestilent, pestilential, mortiferous, necrotic

Nearby words

  1. leta,
  2. letch,
  3. letchworth,
  4. letdown,
  5. letha,
  6. lethal chamber,
  7. lethal dose,
  8. lethal factor,
  9. lethal gene,
  10. lethal midline granuloma

Origin of lethal

1575–85; < Latin lētālis, equivalent to lēt(um) death + -ālis -al1; spelling (hence pronunciation) with -h- by association with Greek lḗthē oblivion
Related forms
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for lethal

British Dictionary definitions for lethal

lethal

/ (ˈliːθəl) /

adjective

able to cause or causing death
of or suggestive of death
Derived Formslethality (liːˈθælɪtɪ), nounlethally, adverb

Word Origin for lethal

C16: from Latin lēthālis, from lētum death
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for lethal

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
Medicine definitions for lethal

lethal

[ lē′thəl ]

adj.

Capable of causing death.
Of, relating to, or causing death.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.