Mimosa is a genus of about 600 species of herbs and shrubs, in the mimosoid clade of the legume family Fabaceae. Species are native to the Americas, from North Dakota to northern Argentina, and to eastern Africa as well as the Indian subcontinent and Indochina. The generic name is derived from the Greek word μῖμος (mimos), an "actor" or "mime", and the feminine suffix -osa, "resembling", suggesting its 'sensitive leaves' which seem to 'mimic conscious life'.

The Mimosoideae are a traditional subfamily of trees, herbs, lianas, and shrubs in the pea family (Fabaceae) that mostly grow in tropical and subtropical climates. They are typically characterized by having radially symmetric flowers, with petals that are twice divided (valvate) in bud and with numerous showy, prominent stamens.