deathly

American  

[deth-lee] / ˈdɛθ li /

adjective

1. causing death; deadly; fatal.

2. like death.

   a deathly silence.

3. of, relating to, or indicating death; morbid.

   a deathly odor from the sepulcher.

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adverb

1. in the manner of death.

2. very; utterly.

   deathly afraid.

deathly British  

/ ˈdɛθlɪ /

adjective

1. deadly

2. resembling death

   a deathly quiet

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Other Word Forms

• deathliness noun
• predeathly adjective

Etymology

Origin of deathly

before 1000; Middle English dethlich, Old English dēathlīc. See death, -ly

Explanation

Something that's deathly reminds you of death. If you dress up as a ghost for Halloween, the makeup on your cheeks might turn your face a deathy shade of gray. A spooky silence can be described as deathly silent, and an unhealthy skin color is often called a deathly pallor. When you shiver, your friend might take your hand and say, "You have a deathly chill." An older meaning of deathly, used especially in literature, was "causing death." The Old English root word is deaþlic, "mortal."

Example Sentences

The atmosphere among those who came to mourn the tragedy was deathly quiet.

From Barron's • Jan. 1, 2026

Brad Jacobs, the billionaire CEO of building-products distributor QXO, devoted a chapter in his book to “electric meetings,” noting many gatherings are deathly dull and full of passive listeners.

From The Wall Street Journal • Oct. 28, 2025

He could have been totally fine, or he could have gotten deathly ill.

From Salon • Aug. 16, 2025

When Charlie Hopkins thinks back to the three years he spent in one of America's most famous prisons, he remembers the "deathly quiet" the most.

From BBC • May 10, 2025

A deathly silence sucked the life out of the air as every last Glader stared at the row of windows, at the row of observers.

From "The Maze Runner" by James Dashner