Genus Quassia, a small group of trees and shrubs from the Simaroubaceae family, is also known by other names. Some commonly used synonyms include Picrasma, Simaba, and Castela - all of which are used interchangeably with Genus Quassia, depending on the particular species being referred to. Another synonym often used is Quassia Amara, which is a species native to South America and has a long history of use in traditional medicine. This group of plants is known for their bitter properties, which have been used for medicinal purposes for generations. While the exact synonym used may depend on the specific context, all of these terms refer to various members of the Genus Quassia plant group.