First Known Use: circa 1604
Dictionary
1lethal
adjective le·thal \ˈlē-thəl\
: causing or able to cause death
Full 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>
— le·thal·i·ty \lē-ˈtha-lə-tē\ noun
— le·thal·ly \ˈlē-thə-lē\ adverb
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Origin of LETHAL
Latin letalis, lethalis, from letum death
Related to LETHAL
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>.
2lethal
noun
Definition of LETHAL
1
: an abnormality of genetic origin causing the death of the organism possessing it
2
First Known Use of LETHAL
1917
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