1
Mayday(noun, information, sign, notice, alert)
1
SOS(noun, information, sign, notice, alert)
1
active(sharp, bright, lively, alert, aware)
1
admonition(information, sign, notice, alert, caution)
1
advice(information, sign, notice, alert, hint)
1
alarm(information, sign, notice, alert, caution)
1
alert(adjective, sharp, sign, notice, bright)
1
all ears(expression, sharp, bright, lively, alert)
1
attentive(sharp, bright, lively, alert, aware)
1
augury(information, sign, notice, alert, hint)
1
be alert(verb, see, mind, notice, spot)
1
be careful(verb, see, mind, notice, spot)
1
be on guard(verb, see, mind, notice, spot)
1
be wary(verb, mind, notice, spot, avoid)
1
beware(verb, mind, notice, spot, avoid)
1
bright(sharp, lively, active, alert, aware)
1
cagey(sharp, bright, lively, active, alert)
1
careful(sharp, bright, lively, alert, aware)
1
check out(verb, expression, phrasal verb, mind, notice)
1
circumspect(sharp, bright, lively, alert, attentive)
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APASmart Define. (2011). heads up thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/heads_up/thesaurus/synonyms
ChicagoSmart Define. 2011. "heads up thesaurus" https://smartdefine.org/heads_up/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2011, heads up thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/heads_up/thesaurus/synonyms>.
MLASmart Define. "heads up thesaurus" 24 May 2011. Web. 20 September 2026. <https://smartdefine.org/heads_up/thesaurus/synonyms>