The word "timer" refers to a device or tool that measures a specific period of time. However, there are several synonyms for this word that can be used interchangeably. Some of the synonyms include "clock," "watch," "chronometer," "stopwatch," and "countdown." These words imply the measure of time, but each carries a different connotation. For example, a countdown is a timer that indicates the time left until an event occurs. On the other hand, a chronometer is a timer that is used to measure time with different units or systems. Using synonyms for the word "timer" can add variety and depth to one's writing or speech.