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Webster 1913 Edition
Alert
A-lert′
(ȧ-lẽrt′)
, Adj.
[F.
alerte
, earlier à l’erte
on the watch, fr. It. all' erta
on the watch, prop. (standing) on a height, where one can look around; erta
a declivity, steep, erto
steep, p. p. of ergere
, erigere
, to erect, raise, L. erigere
. See Erect
.] 1.
Watchful; vigilant; active in vigilance.
2.
Brisk; nimble; moving with celerity.
An
alert
young fellow. Addison.
Syn. – Active; agile; lively; quick; prompt.
A-lert′
,Noun.
(Mil.)
An alarm from a real or threatened attack; a sudden attack; also, a bugle sound to give warning.
“We have had an alert.” Farrow.
On the alert
, on the lookout or watch against attack or danger; ready to act.
Webster 1828 Edition
Alert
ALERT'
, a.1.
Watchful; vigilant; active in vigilance. hence the military phrase, upon the alert, upon the watch, guarding against surprise or danger.2.
Brisk; nimble; moving the celerity.