An organ unique to the cactus family. A modified sideshoot, the areole is usually cushionlike and carries hairs and/or spines. From the areoles arise flowers and offsets; each areole flowers only once.
a space between the threads of a net; in Cactaceae, a cluster of hairs/spines/bristles borne at the node of a leafless stem; in Mimosaceae (for example), a distinct, oblong or elliptical area on the face of a seed, bounded by a fine line; on leaf laminas: the space bounded by the finest veins. adj. areolate.
An organ common to the entire cacti family. Usually circular or oval, areoles are found along the stems of the plant. This areole is the structure from which spines grow, flowers will bud and new stems will branch.
Areoles are the distinctive feature of cacti, and identify them as a separate family from other succulent plants. Areoles give rise to spines or, on certain cacti, small, detachable glochids which are an additional form of protection. The areoles on cacti are clearly visible.