| Main Entry: | fire alarm |
| Part of Speech: | noun |
| Definition: | alarm warning of fire |
| Synonyms: | danger signal, emergency alarm, fire bell, heat sensor, siren, smoke alarm, smoke detector, sprinkler system |
| Main Entry: | distress signal |
| Part of Speech: | noun |
| Definition: | internationally recognized signal requesting help |
| Synonyms: | Mayday, SOS, alarm, burglar alarm, call for help, danger signal, fire alarm, flare, mayday, notice to mariners, signal of distress, warning signal |
| Main Entry: | smoke detector |
| Part of Speech: | noun |
| Definition: | alarm that senses smoke or fire |
| Synonyms: | danger signal, emergency alarm, fire alarm, fire bell, fire detector, heat sensor, siren, smoke alarm |
| Main Entry: | alarm bell |
| Part of Speech: | noun |
| Definition: | warning bell |
| Synonyms: | burglar alarm, danger signal, fire alarm, tocsin |