macadamia

Edible nut of a group of trees native to Australia (especially M. ternifolia), and cultivated in Hawaii, South Africa, Zimbabwe, and Malawi. The nuts are slow-growing; they are harvested when they drop. (Genus Macadamia, family Proteaceae.)

In Australia, the most important commercial species are M. integrifolia (Queensland only) and M. tetraphylla. The northern Queensland species M. whelanii has seeds containing dangerous levels of prussic acid, but Aborigines used them as a food source after grinding, washing, and cooking them.