(historical) A bell rung to signal danger or emergency. / A bell which is rung to indicate a pre-arranged time, especially to mark a desired moment for waking up, performing a specific action etc.

(figuratively, usually in the plural) A sudden awareness of danger. / Used other than figuratively or idiomatically: see alarm, bell.

plural of alarm clock

plural of burglar alarm

(literally) A warning signal (such as the call of sentry, the ringing of a bell, or the shriek of a siren) which turns out to have been given erroneously.

A device attached to a steam boiler to indicate excessive steam pressure or insufficient water.

plural of alarm gauge

plural of alarm substance

plural of false alarm

plural of alarm-bell