Evergreen trees or shrubs with yellow or reddish sap. Leaves, fruits and young parts of stems with brown peltate hairs.
It is a strictly neotropical family with five species in a single genus. Bixa orellana L., yielding a reddish food colouring commercially known as annatto, is widely cultivated and often naturalised throughout the tropics.
Annatto is yielded from the sarcotesta and consists mainly of bixin. It has many desirable properties such as resistance to light, heat, etc. and is widely used as a food colouring agent and also as a spice.
The plant was probably cultivated already in pre-Columbian times and, among its various applications, the use as a body paint in religious ceremonies or simply as a sun protection has the been most important. Since the leaves are not eaten by cows or goats, B. orellana is also used for fences.