In an alarming way, frighteningly. / Causing fear or concern. / To an extent that causes alarm.

present participle of alarm

causing apprehension, fear or alarm; frightening

(normally archaic) A danger signal or warning. / A call to arms.

(archaic) To sound alarums, to sound an alarm.

A horn on a fire alarm that sounds in case of fire, either automatically when the system detects fire or manually when the alarm is pulled, to alert the occupants of a building or complex of the hazard.

plural of alarm

Third-person singular simple present indicative form of alarm

One who causes others to become alarmed without cause.

Of or relating to causing others to become alarmed without cause.