Klaxons are powerful horns that produce loud and harsh sounds, often used as warning signals. Synonyms for klaxons can include sirens, hooters, buzzers, alarms, and honkers. Each of these words can be used to describe a range of warning devices, from the ear-piercing wail of a police siren, to the gentle beep of a car alarm. Depending on the context, other words such as whistles, bells, and chimes can also be used as synonyms for klaxons. These words are often used interchangeably, but can convey different levels of urgency or intensity depending on the situation.