1) Arthropod genus 2) Genus locusta 3) Swarming insect genus 
Locusta (or Lucusta) was notorious in Ancient Rome for her skill in concocting poisons. According to ancient historians, in AD 54 Locusta was hired by Agrippina the Younger to supply a poisoned dish of mushrooms for the murder of Emperor Claudius. In 55, she was convicted of poisoning another victim, but Nero rescued her from execution and in retu...
• (n.) The spikelet or flower cluster of grasses.
(from the article `serial murder`) Serial murder has occurred throughout history. One of the earliest documented cases involved Locusta, a Roman woman hired by Agrippina the Younger, ...
Lo·cus'ta noun [ New Latin : confer locuste .] (Botany) The spikelet or flower cluster of grasses. Gray. 
[n] - a genus of Acrididae
genus Locusta noun a genus of Acrididae