1

lethal

adjective le·thal \ ˈlē-thəl \
Updated on: 21 Nov 2017

Definition of lethal

1 a : of, relating to, or causing death
  • death by lethal injection
b : capable of causing death
  • lethal chemicals
2 : gravely damaging or destructive : devastating
  • a lethal attack on his reputation
3 : very potent or effective
  • a lethal fastball
; also : having a high alcohol content
  • a lethal rum punch

lethality

play \lē-ˈtha-lə-tē\ noun

lethally

play \ˈlē-thə-lē\ adverb

Examples of lethal in a Sentence

  1. a potentially lethal dose of a drug

  2. He was sentenced to death by lethal injection.

Recent Examples of lethal from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lethal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of lethal

Latin letalis, lethalis, from letum death

Synonym Discussion of lethal

deadly, mortal, fatal, lethal mean causing or capable of causing death. deadly applies to an established or very likely cause of death.
    • a deadly disease
mortal implies that death has occurred or is inevitable.
    • a mortal wound
fatal stresses the inevitability of what has in fact resulted in death or destruction.
    • fatal consequences
lethal applies to something that is bound to cause death or exists for the destruction of life.
    • lethal gas

2

lethal

noun

Definition of lethal

1 : an abnormality of genetic origin causing the death of the organism possessing it

Origin and Etymology of lethal


LETHAL Defined for English Language Learners

lethal

adjective

Definition of lethal for English Language Learners

  • : causing or able to cause death


Medical Dictionary

1

lethal

adjective le·thal \ ˈlē-thəl \

medical Definition of lethal

: of, relating to, or causing death
  • a lethal injury
; also : capable of causing death
  • lethal chemicals
  • a lethal dose

lethality

play \lē-ˈthal-ət-ē\ noun plural lethalities

lethally

adverb

2

lethal

noun

medical Definition of lethal

1 : an abnormality of genetic origin causing the death of the organism possessing it usually before maturity


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