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Dictionary.com

warning signal

NOUN
alarum
Synonyms
STRONG
alert bell signal siren warning
WEAK
call to arms
NOUN
beacon
Synonyms
STRONGEST
flare lantern radar
STRONG
alarm alert balefire beam bonfire guidepost heliograph lamp lighthouse lodestar pharos rocket sign watchtower
WEAK
signal fire smoke signal
NOUN
distress signal
Synonyms
WEAK
Mayday SOS alarm burglar alarm call for help danger signal fire alarm flare notice to mariners signal of distress
NOUN
high sign
Synonyms
WEAK
alert signal the nod the wink

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.

Analysts said the data is a warning signal.

From Barron's • Mar. 24, 2026

Historically, the absence of a year-end rally has carried a warning signal.

From MarketWatch • Dec. 21, 2025

In this condition, the warning signal doesn’t stop even after the injury has healed.

From Science Daily • Oct. 10, 2025

The Department for Health and Social Care said that genomics - the study of genes - and AI would be used to "revolutionise prevention" and provide faster diagnoses and an "early warning signal for disease".

From BBC • Jun. 21, 2025

He broke off as Pima flashed a warning signal.

From "Ship Breaker" by Paolo Bacigalupi