deadlier; deadliest
1
: likely to cause or capable of producing death
deadly poison
2
a
: aiming to kill or destroy : implacable
a deadly enemy
b
: highly effective
a deadly exposé
c
: unerring
a deadly marksman
d
: marked by determination or extreme seriousness
3
a
: tending to deprive of force or vitality
a deadly habit
b
: suggestive of death especially in dullness or lack of animation
deadly bores
a deadly conversation
4
: very great : extreme
deadliness
noun
Synonyms
Adjective
Adverb
- achingly
- almighty
- archly
- awful
- awfully
- badly
- beastly
- blisteringly
- bone
- colossally
- corking
- cracking
- damn
- damned
- dang
- desperately
- eminently
- enormously
- especially
- ever
- exceedingly
- exceeding
- extra
- extremely
- fabulously
- fantastically
- far
- fiercely
- filthy
- frightfully
- full
- greatly
- heavily
- highly
- hugely
- immensely
- incredibly
- intensely
- jolly
- majorly
- mightily
- mighty
- monstrous [chiefly dialect]
- mortally
- most
- much
- particularly
- passing
- rattling
- real
- really
- right
- roaring
- roaringly
- seriously
- severely
- so
- sore
- sorely
- spanking
- specially
- stinking
- such
- super
- supremely
- surpassingly
- terribly
- that
- thumping
- too
- unco
- uncommonly
- vastly
- very
- vitally
- way
- whacking
- wicked
- wildly
Examples of deadly in a Sentence
Adjective
the world's most deadly snake
a more deadly form of the disease
They launched a deadly attack.
Officers are allowed to use deadly force if necessary.
She shoots with deadly accuracy.
a basketball player with deadly aim
A deadly silence followed his question.
The two gang leaders are deadly enemies.
He spoke with deadly seriousness.
Adverb
I'm deadly serious about making an offer on the house.
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Recent Examples on the Web
CBS News, 19 Nov. 2023
Officers responded to an assault with a deadly weapon call near 54th Street and Manhattan Place about 11:55 p.m. Friday, according to the Los Angeles Police Department.
—Brennon Dixson, Los Angeles Times, 18 Nov. 2023
As noted by The Atlantic, this very conspiracy theory was espoused by the man who murdered 11 people in a Pittsburgh synagogue in 2018, the deadliest anti-Semitic attack on U.S. soil.
—Kylie Robison, Fortune, 17 Nov. 2023
However, the animals that lived alongside ancient humans were less cute and cuddly and more fierce and deadly.
—Donna Sarkar, Discover Magazine, 17 Nov. 2023
Season 6 of The Crown depicts Diana's life right before the deadly crash and its aftermath, but PEOPLE confirmed in October 2022 that the series would not show the actual moment of impact.
—Stephanie Kaloi, Peoplemag, 17 Nov. 2023
At the time, law enforcement said the soldiers had staged a deadly and premeditated assault on Houston’s white population.
—Teresa Nowakowski, Smithsonian Magazine, 16 Nov. 2023
Hines is one of 39 people known to survive the deadly leap.
—Kara Nelson, CNN, 19 Nov. 2023
Lebanon’s Hezbollah weighs dueling appeals: Ease attacks or escalate
And both sides have started using deadlier weapons.
—Liz Sly, Washington Post, 19 Nov. 2023
Assaf Orion, Foreign Affairs, 3 Nov. 2023
Or around the other way around: a light, comic scene suddenly takes this sharp turn and becomes deadly serious.
—Selome Hailu, Variety, 8 Nov. 2023
Investigators do know, however, one factor that made the fires so deadly: invasive grass that had transformed the island into a giant tinderbox.
—Shi En Kim, Smithsonian Magazine, 15 Aug. 2023
Waves from Lee continue to cause rough seas and potentially deadly rip currents up and down the Eastern Seaboard and Atlantic Canada.
—Leigh Morgan, al, 16 Sep. 2023
And sometimes the heat can turn deadly, especially for those who work in the agricultural industry.
—Jake Frederico, The Arizona Republic, 4 Sep. 2023
The flooding is unusual for the region — one of the last times floods this deadly hit North Africa was in 1927 in Algeria.
—Dan Stillman, Washington Post, 12 Sep. 2023
State Police investigating deadly stabbing onboard Greyhound bus traveling from Pittsburgh to Washington, D.C.
—Shanelle Kaul, CBS News, 3 Aug. 2023
Lee will continue to churn up rough seas and cause potentially deadly rip currents along the U.S. East Coast through the weekend.
—Leigh Morgan, al, 15 Sep. 2023
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Adjective
The deadly conflict between Israel and Hamas has entered week seven, with no clear end in sight, as Israeli forces intensify efforts to eliminate Hamas in Gaza.
—CBS News, 19 Nov. 2023
Officers responded to an assault with a deadly weapon call near 54th Street and Manhattan Place about 11:55 p.m. Friday, according to the Los Angeles Police Department.
—Brennon Dixson, Los Angeles Times, 18 Nov. 2023
As noted by The Atlantic, this very conspiracy theory was espoused by the man who murdered 11 people in a Pittsburgh synagogue in 2018, the deadliest anti-Semitic attack on U.S. soil.
—Kylie Robison, Fortune, 17 Nov. 2023
However, the animals that lived alongside ancient humans were less cute and cuddly and more fierce and deadly.
—Donna Sarkar, Discover Magazine, 17 Nov. 2023
Season 6 of The Crown depicts Diana's life right before the deadly crash and its aftermath, but PEOPLE confirmed in October 2022 that the series would not show the actual moment of impact.
—Stephanie Kaloi, Peoplemag, 17 Nov. 2023
At the time, law enforcement said the soldiers had staged a deadly and premeditated assault on Houston’s white population.
—Teresa Nowakowski, Smithsonian Magazine, 16 Nov. 2023
Hines is one of 39 people known to survive the deadly leap.
—Kara Nelson, CNN, 19 Nov. 2023
Lebanon’s Hezbollah weighs dueling appeals: Ease attacks or escalate
And both sides have started using deadlier weapons.
—Liz Sly, Washington Post, 19 Nov. 2023
Adverb
Potential warning signs were ignored, dismissed, or downplayed, and misguided security priorities may have made the attack more deadly.
—Assaf Orion, Foreign Affairs, 3 Nov. 2023
Or around the other way around: a light, comic scene suddenly takes this sharp turn and becomes deadly serious.
—Selome Hailu, Variety, 8 Nov. 2023
Investigators do know, however, one factor that made the fires so deadly: invasive grass that had transformed the island into a giant tinderbox.
—Shi En Kim, Smithsonian Magazine, 15 Aug. 2023
Waves from Lee continue to cause rough seas and potentially deadly rip currents up and down the Eastern Seaboard and Atlantic Canada.
—Leigh Morgan, al, 16 Sep. 2023
And sometimes the heat can turn deadly, especially for those who work in the agricultural industry.
—Jake Frederico, The Arizona Republic, 4 Sep. 2023
The flooding is unusual for the region — one of the last times floods this deadly hit North Africa was in 1927 in Algeria.
—Dan Stillman, Washington Post, 12 Sep. 2023
State Police investigating deadly stabbing onboard Greyhound bus traveling from Pittsburgh to Washington, D.C.
—Shanelle Kaul, CBS News, 3 Aug. 2023
Lee will continue to churn up rough seas and cause potentially deadly rip currents along the U.S. East Coast through the weekend.
—Leigh Morgan, al, 15 Sep. 2023
See More
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'deadly.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Word History
Phrases Containing deadly
Dictionary Entries Near deadly
Cite this Entry
“Deadly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deadly. Accessed 2 Dec. 2023.
Copy Citation
Kids Definition
deadly
2 of 2 adverb1
: suggesting death
deadly pale
2
: to a very great degree
deadly dull
Medical Definition
Legal Definition
deadly
adjective
dead·ly
deadlier; deadliest
: likely to cause or capable of causing death
also
: dangerous sense 2
Note: Deadly and dangerous are sometimes used interchangeably, especially in connection with weapons or instruments.
More from Merriam-Webster on deadly
Nglish: Translation of deadly for Spanish Speakers
Britannica English: Translation of deadly for Arabic Speakers
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