adjective dead·ly \ˈded-lē\

: causing or able to cause death

: extremely accurate and effective

: extreme or complete


Full Definition of DEADLY

:  likely to cause or capable of producing death <deadly poison>
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
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>
:  very great :  extreme
dead·li·ness noun

Examples of DEADLY

  1. the world's most deadly snake
  2. a more deadly form of the disease
  3. They launched a deadly attack.
  4. Officers are allowed to use deadly force if necessary.
  5. She shoots with deadly accuracy.
  6. a basketball player with deadly aim
  7. A deadly silence followed his question.
  8. The two gang leaders are deadly enemies.
  9. He spoke with deadly seriousness.

First Known Use of DEADLY

before 12th century

Synonym Discussion of DEADLY

deadly, mortal, fatal, lethal mean causing or capable of causing death. deadly applies to an established or very likely cause of death <a deadly disease>. mortal implies that death has occurred or is inevitable <a mortal wound>. fatal stresses the inevitability of what has in fact resulted in death or destruction <fatal consequences>. lethal applies to something that is bound to cause death or exists for the destruction of life <lethal gas>.

Rhymes with DEADLY



: extremely or completely

Full Definition of DEADLY

archaic :  in a manner to cause death :  mortally
:  suggesting death
:  extremely <deadly serious>

Examples of DEADLY

  1. <I'm deadly serious about making an offer on the house.>

First Known Use of DEADLY

before 12th century


adjective dead·ly \ˈded-lē\   (Medical Dictionary)

Medical Definition of DEADLY

:  likely to cause or capable of causing death <a deadly disease> <a deadly poison> <a deadly instrument>
dead·li·ness \-nəs\ noun


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May 28, 2015
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