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
1
: an abnormality of genetic origin causing the death of the organism possessing it
2
Synonyms
Examples of lethal in a Sentence
Adjective
a potentially lethal dose of a drug
He was sentenced to death by lethal injection.
Recent Examples on the Web
Laura Baisas, Popular Science, 7 Nov. 2024
Snares, set to capture other animals for bushmeat, pose a lethal risk to saolas, who often fall victim to these traps accidentally.
Cheap and easy to deploy, snares blanket the forests, endangering not just the saola but a wide range of species.
—Scott Travers, Forbes, 5 Nov. 2024
Kylie Bourne, Discover Magazine, 14 Sep. 2015
Almost 8 of 10 lethal overdose victims had no contact with the agency before their deaths, the report found.
—Washington Post, 4 Sep. 2020
See all Example Sentences for lethal 
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Adjective
The arachnids have become the lethal poisonous animal in Brazil and has increased the demand for antivenom.
—Laura Baisas, Popular Science, 7 Nov. 2024
Snares, set to capture other animals for bushmeat, pose a lethal risk to saolas, who often fall victim to these traps accidentally.
Cheap and easy to deploy, snares blanket the forests, endangering not just the saola but a wide range of species.
—Scott Travers, Forbes, 5 Nov. 2024
Noun
There are already concerns in Australia about the rate of escalation of force at some protests and about the use of less-than-lethal weaponry itself.
—Kylie Bourne, Discover Magazine, 14 Sep. 2015
Almost 8 of 10 lethal overdose victims had no contact with the agency before their deaths, the report found.
—Washington Post, 4 Sep. 2020
See all Example Sentences for lethal
Dictionary Entries Near lethal
Cite this Entry
“Lethal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lethal. Accessed 22 Nov. 2024.
Copy CitationKids Definition
lethal
2 of 2 nounMedical Definition
lethal
1 of 2 adjective
le·thal
ˈlē-thəl 
: of, relating to, or causing death
a lethal injury
also
: capable of causing death
lethal chemicals
a lethal dose
lethally
adverb
lethal
2 of 2 noun1
: an abnormality of genetic origin causing the death of the organism possessing it usually before maturity
2
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