calyx The sepals of a flower, taken as a group. The calyx is usually green in color and protects the flower when it is in bud. When the flower opens, the calyx surrounds the carpels, petals, and stamens, and forms the outer whorl of the perianth. Related category • BOTANY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |