A genus of poisonous fungi of the family Agaricaceæ, characterized by having a volva, an annulus, and white spores. The species resemble edible mushrooms, and are frequently mistaken for them. Amanita muscaria, syn. Agaricus muscarius, is the fly amanita, or fly agaric; and A. phalloides is the death cup.
- Any of various mushrooms in the genus Amanita, many of which are extremely poisonous.