dangerous [ deyn-jer- uh s, deynj-r uh s] Word Origin See more synonyms for dangerous on Thesaurus.com full of danger or risk; causing danger; perilous; risky; hazardous; unsafe. able or likely to cause physical injury: a dangerous criminal. Origin of dangerous 1175–1225; Middle English da(u)ngerous
domineering, fraught with danger <
Old French dangereus
threatening, difficult, equivalent to
-eus -ous Related forms dan·ger·ous·ly, adverb dan·ger·ous·ness, noun non·dan·ger·ous, adjective non·dan·ger·ous·ly, adverb non·dan·ger·ous·ness, noun qua·si-dan·ger·ous, adjective qua·si-dan·ger·ous·ly, adverb sem·i·dan·ger·ous, adjective sem·i·dan·ger·ous·ly, adverb sem·i·dan·ger·ous·ness, noun un·dan·ger·ous, adjective un·dan·ger·ous·ly, adverb
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for undangerous Derived Forms dangerously, adverb dangerousness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Word Origin and History for undangerous dangerous adj.
early 13c., "difficult, arrogant, severe" (the opposite of
affable), from Anglo-French dangerous, Old French dangeros (12c., Modern French dangereux), from danger (see danger).
In Chaucer, it means "hard to please, reluctant to give;" sense of "full of danger, risky" is from late 15c. Other words used in this sense included
dangersome (1560s), dangerful (1540s). Related: Dangerously.
Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with undangerous dangerous
see little knowledge is a dangerous thing; live dangerously.
The American Heritage® Idioms Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.