Subfamily Caesalpinioideae is a subdivision of the legume family Fabaceae. It includes around 200 genera and over 2,000 species of tropical and subtropical trees, shrubs, and lianas. Some synonyms for Subfamily Caesalpinioideae include Caesalpiniaceae, Leguminosae, and Fabaceae (sensu lato). Caesalpiniaceae was formerly used as a separate family, but molecular evidence supported its inclusion in the Fabaceae family. The subfamily is characterized by its zygomorphic flowers, with five petals of differing sizes and shapes. Many species in this subfamily are economically important for timber, firewood, and medicinal uses. Overall, the synonyms for Subfamily Caesalpinioideae reflect the evolution of botanic classification and the intricate relationships between different plant groups.