Seventeen year locust is a common term used for the periodical cicada, a species of cicada that emerges from the ground every 17 years. These insects are found in various regions of the US and are known for their distinct buzzing and clicking sounds. Some synonyms for the seventeen year locust include periodical cicada, 17-year cicada, magicicada, and Brood X cicada. These names are used interchangeably to refer to these fascinating insects that fascinate entomologists and curious observers alike. If you happen to live in an area where periodical cicadas are known to emerge, don't miss the chance to witness one of nature's most amazing phenomena.