adjective
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
Explanation
Use the word dangerous to describe anything that can potentially cause serious harm, like a snarling pit bull or an icy, treacherous road. The earliest meaning of the word dangerous was "difficult or arrogant." When Geoffrey Chaucer wrote "The Canterbury Tales" in the 1300s, he used dangerous to mean "hard to please." Gradually the meaning changed, so that by the late fifteenth century, dangerous meant "liable to cause hurt" or "risky." Just as popular were two other danger-related words that we don't use anymore today: dangersome and dangerful, which at the time could be used interchangeably with dangerous.
Vocabulary lists containing dangerous
Words Every Pirate Should Know
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"Volcano!"
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"Brothers in Hope"
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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.
That means Joshua could enter a Fury fight having spent long spells away from elite-level opposition, whereas Fury showed that he can still navigate 12 rounds against a dangerous, if limited, puncher.
From BBC • Apr. 12, 2026
But Bass and every council member and all their successors need to be reminded that a civic sense of intractability is a dangerous thing.
From Los Angeles Times • Apr. 11, 2026
Takeoff is among the most dangerous moments as missile alerts force passengers to sit tight.
From The Wall Street Journal • Apr. 10, 2026
DHS has boasted about instances when wellness checks reportedly helped a minor escape a dangerous living situation.
From Salon • Apr. 10, 2026
“I was mad that it killed people. I was mad that it was so ugly and dirty … I was mad at how dangerous it was.”
From "Mountain of Fire" by Rebecca E. F. Barone
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.
