Alert

a.	1.	Watchful; vigilant; active in vigilance.
	2.	Brisk; nimble; moving with celerity. An alert young fellow. - Addison.
n.	1.	(Mil.) An alarm from a real or threatened attack; a sudden attack; also, a bugle sound to give warning. On the alert on the lookout or watch against attack or danger; ready to act.

Noun	1.	alert - condition of heightened watchfulness or preparation for action; "bombers were put on alert during the crisis" Synonyms: qui vive
	2.	alert - a warning serves to make you more alert to danger Synonyms: alerting
	3.	alert - an automatic signal (usually a sound) warning of danger Synonyms: alarum, warning signal, alarm
Verb	1.	alert - warn or arouse to a sense of danger or call to a state of preparedness; "The empty house alarmed him"; "We alerted the new neighbors to the high rate of burglaries" Synonyms: alarm
Adj.	1.	alert - very attentive or observant; "an alert and responsive baby is a joy"; "caught by a couple of alert cops"; "alert enough to spot the opportunity when it came"; "constantly alert and vigilant, like a sentinel on duty" Antonyms: unalert - not alert or attentive
	2.	alert - mentally responsive; "an alert mind"
	3.	alert - not unconscious; especially having become conscious; "the patient is now awake and alert" Synonyms: awake
	4.	alert - (usually followed by `to') showing acute awareness; mentally perceptive; "alert to the problems"; "alive to what is going on"; "awake to the dangers of her situation"; "was now awake to the reality of his predicament" Synonyms: awake, alive

(operating system)

alert - /*'l*rt/ An audible and/or visual message intended to inform a system's users or administrators about a change in the operating conditions of that system or about some kind of error condition. In a graphical user interface, an alert would typically be displayed as a small window containing the message and a button to click to dismiss the window.

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