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Dictionary.com

without warning

ADJECTIVE
precipitous/precipitate
Synonyms
WEAK
abrupt breakneck brief frantic gone off half-cocked harum-scarum hasty headlong heedless hurried ill-advised impatient impetuous indiscreet jump the gun madcap off the hip off the top of head plunging precipitant quick rapid rash reckless refractory rushing subitaneous swift unanticipated uncontrolled unexpected unforeseen violent willful
Antonyms
WEAK
careful cautious slow
ADJECTIVE
surprising
Synonyms
STRONGEST
amazing astonishing extraordinary remarkable shocking startling stunning sudden unanticipated unforeseen unpredictable wonderful
STRONG
chance electrifying
WEAK
accidental fortuitous from left field impulsive out of the blue unpredicted
Antonyms
STRONGEST
expected normal ordinary predictable usual
ADJECTIVE
unheralded
Synonyms
WEAK
unannounced unanticipated unpredicted
Antonyms
WEAK
announced celebrated expected glorified predicted recognized
ADVERB
short
Synonyms
STRONG
suddenly unawares
WEAK
aback by surprise forthwith sudden unanticipatedly unaware unexpectedly without delay without hesitation
ADVERB
suddenly
Synonyms
STRONGEST
abruptly all of a sudden quickly swiftly
STRONG
short
WEAK
aback all at once asudden forthwith on spur of moment sudden unanticipatedly unaware unawares
Antonyms
WEAK
expectedly slowly
ADVERB
swiftly
Synonyms
STRONGEST
expeditiously hastily promptly quickly rapidly speedily
STRONG
fleetly
WEAK
apace double-quick flat-out full tilt hotfoot hurriedly posthaste quick swift
Antonyms
STRONGEST
slowly
WEAK
sluggishly
ADVERB
swiftly/swift
Synonyms
WEAK
apace double-quick expeditiously flat-out fleetly full tilt hastily hurriedly in no time posthaste promptly quick quickly rapidly speedily without losing time
Antonyms
WEAK
slowly sluggishly

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.

"For us, this happened without warning," she says.

From BBC • May 5, 2026

Still, big earthquakes can happen without warning, and it’s part of the risk of living in places like California and Nevada.

From Los Angeles Times • May 4, 2026

The White House keeps claiming that victory is near on Iran, which keeps people aware that the blockage of the Strait of Hormuz could end without warning, Lynch said.

From MarketWatch • Apr. 30, 2026

Bear markets rarely emerge without warning, not that one is necessarily at hand, but subtle signs of distribution often build quietly before becoming more pronounced.

From Barron's • Apr. 2, 2026

By this time I’d started to cry, without warning, and to sit beside the bedroom window, staring out.

From "The Handmaid's Tale" by Margaret Atwood