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Synonyms

dangerous

American  
[deyn-jer-uhs, deynj-ruhs] / ˈdeɪn dʒər əs, ˈdeɪndʒ rəs /

adjective

  1. full of danger danger or risk; causing danger; danger; perilous; risky; hazardous; unsafe.

  2. able or likely to cause physical injury.

    a dangerous criminal.


dangerous British  
/ ˈdeɪndʒərəs /

adjective

  1. causing danger; perilous

"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

dangerous Idioms  
  1. see little knowledge is a dangerous thing; live dangerously.


Other Word Forms

  • dangerously adverb
  • dangerousness noun
  • nondangerous adjective
  • nondangerously adverb
  • nondangerousness noun
  • quasi-dangerous adjective
  • quasi-dangerously adverb
  • semidangerous adjective
  • semidangerously adverb
  • semidangerousness noun
  • undangerous adjective
  • undangerously adverb

Etymology

Origin of dangerous

First recorded in 1175–1225; Middle English da(u)ngerous “domineering, fraught with danger,” from Old French dangereus “threatening, difficult,” equivalent to dangier ( danger ) + -eus -ous

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.

It has been a dangerous holiday season for avalanches in the high Sierra.

From Los Angeles Times

Later in the record, a growling bass clarinet on “I Need You” makes the jazzy beat sound dangerous, like slow exhalations from a sleeping dragon.

From The Wall Street Journal

However, the American Academy of Pediatrics criticised the recommendation, describing it as "dangerous and unnecessary."

From BBC

How efficiently viruses move between cells plays a major role in how dangerous an infection becomes.

From Science Daily

Hyundai said the robots will help ease physical strain on human workers, handle potentially dangerous tasks and pave the way for wider use of the technology.

From BBC