dangerous

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.

Definitions of dangerous
1

adj involving or causing danger or risk; liable to hurt or harm

“a dangerous criminal”
“a dangerous bridge”
“unemployment reached dangerous proportions”
Synonyms:
unsafe
breakneck
moving at very high speed
chanceful, chancy, dicey, dodgy
of uncertain outcome; especially fraught with risk
desperate
(of persons) dangerously reckless or violent as from urgency or despair
hazardous, risky, wild
involving risk or danger
insidious
intended to entrap
mordacious
biting or given to biting
on the hook
caught in a difficult or dangerous situation
parlous, perilous, precarious, touch-and-go
fraught with danger
self-destructive, suicidal
dangerous to yourself or your interests
treacherous, unreliable
dangerously unstable and unpredictable
insecure, unsafe
lacking in security or safety
vulnerable
susceptible to attack
Antonyms:
safe
free from danger or the risk of harm
harmless
not causing or capable of causing harm
uninjured
not injured physically or mentally
fail-safe
eliminating danger by compensating automatically for a failure or malfunction
off the hook
freed from danger or blame or obligation
risk-free, riskless, unhazardous
thought to be devoid of risk
safe and sound, unhurt
free from danger or injury
secure
free from danger or risk
invulnerable
immune to attack; impregnable
show more antonyms...

adj causing fear or anxiety by threatening great harm

“a dangerous operation”
Synonyms:
grave, grievous, life-threatening, serious, severe
critical
being in or verging on a state of crisis or emergency

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