Acacia is the generic name for a genus of pod-bearing trees and shrubs in the subfamily Mimosoideae, which belongs to the family Fabaceae.

Acacias are found in tropical and subtropical regions worldwide, and in general they have compound pinnate leaves. There are an estimated 1,300 species, with many being thorny.

The flowers have very small petals, that are arranged in dense globular or cylindrical clusters. In most species, these small flowers are yellow.