woodsorrel: A genus of the pentagynia order, belonging to the decandria clas of plants; and in the natural method ranking under the 14th order, Gruinariae. The calyx is pentaphyllous; the petals connected at the heels; the capsule pentagonal, and opening at the angles. There are seven species; of which the only remarkable is the acetofella, or common wood sorrel. This grows naturally in moist shady woods, and at the sides of hedges in many parts of Britain, and is seldom admitted into gardens. The roots are composed of many feely joints, which propagate in great plenty. The leaves arise immediately from the roots upon single long footstalks, and are composed of three heart-shaped lobes. They are grateful acid, and of use in the scurvy and other putrid disorders.