Any fungus of the family Agaricaceae, including the familiar commercially grown mushroom. Agarics have spore-bearing cells (basidia) located on thin sheets called gills. Best known of the agarics is the genus Agaricus (Psalliota), which includes some 60 species, the most prominent being the edible meadow, or field, mushroom, A. campestris, and the common cultivated mushroom, A. bisporus