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Synonyms

deadly

American  
[ded-lee] / ˈdɛd li /

adjective

deadlier, deadliest
  1. causing or tending to cause death; fatal; lethal.

    a deadly poison.

  2. aiming to kill or destroy; implacable.

    a deadly enemy.

  3. like death.

    a deadly pallor.

  4. excruciatingly boring.

    The dinner party was absolutely deadly.

    Synonyms:
    dreary, tedious, dull
  5. excessive; inordinate.

    deadly haste.

  6. extremely accurate.

    Annie Oakley was a deadly shot.


adverb

  1. in a manner resembling or suggesting death.

    deadly pale.

  2. excessively; completely.

    deadly dull.

deadly British  
/ ˈdɛdlɪ /

adjective

  1. likely to cause death

    deadly poison

    deadly combat

  2. informal extremely boring

"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

adverb

  1. like death in appearance or certainty

    deadly pale

    a deadly sleep

"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

Related Words

See fatal.

Other Word Forms

  • deadliness noun
  • nondeadly adjective

Etymology

Origin of deadly

First recorded before 900; Middle English deedli(ch), Old English dēadlīce; dead, -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.

The United Nations rights chief called Friday for answers after a deadly strike on an Iranian elementary school, as a media investigation concluded the United States was most likely responsible.

From Barron's

Sri Lanka on Friday denounced the toll of the Mideast fighting, as the nation opened its arms to over 200 Iranian sailors who sought help after a deadly torpedo strike on another of Iran's ships.

From Barron's

Malaria continues to rank among the deadliest infectious diseases worldwide.

From Science Daily

Nepal votes Thursday for a new parliament, six months after deadly anti-corruption protests toppled the government -- a high-stakes showdown between an entrenched old guard and a powerful youth movement.

From Barron's

The disaster was the deadliest for the Argentine navy in peacetime.

From Barron's