How to say "alarm" in Japanese

Choosing the right word

警報けいほうCommon
nounCovers the warning sense of 'alarm': a signal or alert issued to warn of danger such as fire, storms, or intrusion. Think of headlines about alerts being issued rather than a physical device.
その警報けいほうで皆みな部屋へやから飛び出とびだした。↗
The alarm sent everyone rushing out of the room.
恐慌きょうこうCommon
nounCovers the emotional sense of 'alarm', meaning panic or scare. In this sense it is a formal word; it also names economic panics. Seldom the word for an alarm sound or device—use it when 'alarm' means fear or widespread panic.
警報器けいほうきCommon
nounRefers to the alarm device or apparatus itself—fire, burglar, or railroad-crossing alarms. Use this when 'alarm' means the machine that detects danger and sounds the warning, and it can also mean a sensor.
２階かいで朝あさ早はやい時間じかんに警報器けいほうきが鳴なっているのが聞きこえた。↗
The alarm was heard ringing at an early hour on the second floor.
警笛けいてきCommon
nounMeans a horn, whistle, or foghorn—an audible signal blown to warn or alert. For 'alarm' in the sense of a sounding device like a car horn, this fits; for the warning message itself, 警報 is usually the word you want.

Use 警報 for a warning signal or alert, 警報器 for the alarm device itself, 警笛 for a horn or whistle, and 恐慌 for alarm in the sense of panic.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese equivalents

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