alert vs burglar alarm

alert and burglar alarm both are nouns.

Word	Noun	Adjective	Verb	Adverb
alert	Yes	Yes	Yes	No
burglar alarm	Yes	No	No	No

As nouns, burglar alarm is a hyponym of alert; that is, burglar alarm is a word with a more specific, narrower meaning than alert:

Other hyponyms of alert include torpedo, air alert, fire alarm, foghorn, fogsignal, horn, red flag, siren, alarm bell, tocsin.

alert (noun)	burglar alarm (noun)
a warning serves to make you more alert to danger	a warning device that is tripped off by the occurrence of a burglary
an automatic signal (usually a sound) warning of danger	a loud warning signal produced by a burglar alarm
condition of heightened watchfulness or preparation for action

alert (adjective)	burglar alarm (adjective)
engaged in or accustomed to close observation
mentally perceptive and responsive
quick and energetic

alert (verb)	burglar alarm (verb)
warn or arouse to a sense of danger or call to a state of preparedness