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Synonyms

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.

adverb

  1. in the manner of death.

  2. very; utterly.

    deathly afraid.
deathly British  
/ ˈdɛθlɪ /

adjective

  1. deadly

  2. resembling death

    a deathly quiet
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • deathliness noun
  • predeathly adjective

Etymology

Origin of deathly

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Lawren Babek had three cats when she went on a first date in 2008 with a man who said he was deathly allergic.

From The Wall Street Journal • Feb. 2, 2026

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

From Barron's • Jan. 1, 2026

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

From Salon • Aug. 16, 2025

As he struggled with a system, which aimed to preserve secrecy and deepen separation, he didn’t know about a deathly further dimension to the institutional inhumanity.

From BBC • Jul. 12, 2025

Cain’s hand comes up again, and again, the crowd falls deathly silent.

From "An Ember in the Ashes" by Sabaa Tahir

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.