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.
Recent Examples on the Web
Noelle Alviz-Gransee, Kansas City Star, 15 Apr. 2024
This timing makes these storms very dangerous, as research shows nighttime tornadoes are more than twice as deadly as daytime ones.
—Mary Gilbert, CNN, 15 Apr. 2024
This was in retaliation to Israel's deadly attack earlier this month.
—NPR, 15 Apr. 2024
Other fires tied to the company’s equipment include the Zogg fire in 2020, the 2019 Kincade fire and, most notably, the Camp fire in 2018, California’s deadliest.
—Hannah Wiley, Los Angeles Times, 14 Apr. 2024
During Hamas' attack on Israel on Oct. 7, the deadliest assault against Jewish people since the Holocaust, about 1,200 people were killed and over 200 were forcibly taken into Gaza.
—John Kirby, USA TODAY, 14 Apr. 2024
Chained in a finished basement, Alan spends his days thinking of his family, hallucinating his own therapy sessions with former mentor Charlie (David Alan Grier), and trying to get Sam to curb his deadly instincts.
—Tanya Melendez, EW.com, 13 Apr. 2024
But months later, investigators would find out that Rachel Shoaf and Shelia Eddy were hiding a sinister, deadly plot behind their posts and were ultimately responsible for Neese's death.
—Kieran McGirl, ABC News, 12 Apr. 2024
Days after James Crumbley was sentenced to prison for his role in his son's deadly Oxford High School shooting, authorities released audio recordings of jailhouse calls in which Crumbley allegedly threatened Oakland County Prosecutor Karen McDonald.
—Gina Kaufman, Detroit Free Press, 12 Apr. 2024
Antonio Planas, NBC News, 1 Feb. 2024
Pakistan launches deadly airstrikes in Iran Pakistan’s air force launched retaliatory airstrikes in Iran Thursday, killing at least nine people two days after Iran struck at separatist camps in Pakistan.
—Spencer Elliott, USA TODAY, 18 Jan. 2024
Some of the appointments — filmed on bare sets in clean, flat close-up, an aesthetic choice that stresses both their separation from reality and their plain emotional stakes — unfold in deadly earnest.
—Guy Lodge, Variety, 25 Jan. 2024
Texas wildfires turn deadly and keep growing Wildfires in the Texas Panhandle turned deadly, as officials in the city of Borger confirmed one death yesterday afternoon.
—Elizabeth Robinson, NBC News, 29 Feb. 2024
Measles is a highly contagious disease that can lead to complications and turn deadly, according to the CDC.
—Cnn.com Wire Service, The Mercury News, 26 Feb. 2024
The High Desert State Prison investigative services unit, the CDCR deadly force investigation team and the Lassen County District Attorney’s Office are investigating the incident.
—Ishani Desai, Sacramento Bee, 26 Jan. 2024
If new hardline measures are enacted, expect these Mexican cartels—some of the same ones that traffic deadly fentanyl into the U.S.—to turn eye-popping profits.
—TIME, 9 Jan. 2024
That, of course, led to the blind spot that helped make the Hamas attacks so deadly.
—Dahlia Scheindlin, Foreign Affairs, 29 Nov. 2023
Adjective
The city had seen 51 homicides by this time last year, the deadliest year in recorded history.
—Noelle Alviz-Gransee, Kansas City Star, 15 Apr. 2024
This timing makes these storms very dangerous, as research shows nighttime tornadoes are more than twice as deadly as daytime ones.
—Mary Gilbert, CNN, 15 Apr. 2024
This was in retaliation to Israel's deadly attack earlier this month.
—NPR, 15 Apr. 2024
Other fires tied to the company’s equipment include the Zogg fire in 2020, the 2019 Kincade fire and, most notably, the Camp fire in 2018, California’s deadliest.
—Hannah Wiley, Los Angeles Times, 14 Apr. 2024
During Hamas' attack on Israel on Oct. 7, the deadliest assault against Jewish people since the Holocaust, about 1,200 people were killed and over 200 were forcibly taken into Gaza.
—John Kirby, USA TODAY, 14 Apr. 2024
Chained in a finished basement, Alan spends his days thinking of his family, hallucinating his own therapy sessions with former mentor Charlie (David Alan Grier), and trying to get Sam to curb his deadly instincts.
—Tanya Melendez, EW.com, 13 Apr. 2024
But months later, investigators would find out that Rachel Shoaf and Shelia Eddy were hiding a sinister, deadly plot behind their posts and were ultimately responsible for Neese's death.
—Kieran McGirl, ABC News, 12 Apr. 2024
Days after James Crumbley was sentenced to prison for his role in his son's deadly Oxford High School shooting, authorities released audio recordings of jailhouse calls in which Crumbley allegedly threatened Oakland County Prosecutor Karen McDonald.
—Gina Kaufman, Detroit Free Press, 12 Apr. 2024
Adverb
About 10 minutes later, the spree turned deadly, police said.
—Antonio Planas, NBC News, 1 Feb. 2024
Pakistan launches deadly airstrikes in Iran Pakistan’s air force launched retaliatory airstrikes in Iran Thursday, killing at least nine people two days after Iran struck at separatist camps in Pakistan.
—Spencer Elliott, USA TODAY, 18 Jan. 2024
Some of the appointments — filmed on bare sets in clean, flat close-up, an aesthetic choice that stresses both their separation from reality and their plain emotional stakes — unfold in deadly earnest.
—Guy Lodge, Variety, 25 Jan. 2024
Texas wildfires turn deadly and keep growing Wildfires in the Texas Panhandle turned deadly, as officials in the city of Borger confirmed one death yesterday afternoon.
—Elizabeth Robinson, NBC News, 29 Feb. 2024
Measles is a highly contagious disease that can lead to complications and turn deadly, according to the CDC.
—Cnn.com Wire Service, The Mercury News, 26 Feb. 2024
The High Desert State Prison investigative services unit, the CDCR deadly force investigation team and the Lassen County District Attorney’s Office are investigating the incident.
—Ishani Desai, Sacramento Bee, 26 Jan. 2024
If new hardline measures are enacted, expect these Mexican cartels—some of the same ones that traffic deadly fentanyl into the U.S.—to turn eye-popping profits.
—TIME, 9 Jan. 2024
That, of course, led to the blind spot that helped make the Hamas attacks so deadly.
—Dahlia Scheindlin, Foreign Affairs, 29 Nov. 2023
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 19 Apr. 2024.
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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