A summons to arms, as on the approach of an enemy. / Any sound or information intended to give notice of approaching danger; a warning sound to arouse attention; a warning of danger.

(transitive) To call to arms for defense / (transitive) To give (someone) notice of approaching danger / (transitive) To rouse to vigilance and action; to put on the alert.

simple past tense and past participle of alarm

Having an alarm fitted. / Worried; anxious; panicky. / 8: Thomas, the groom, in the act of drinking, put down the jug alarmed before his master. Thomas’s master felt the honour keenly.

present participle of alarm

causing apprehension, fear or alarm; frightening

plural of alarm

Third-person singular simple present indicative form of alarm

The raising of needless alarms.

One who alarms; one who sounds the alarm. / (US, in combination) A multialarm fire of a specified number of alarms.