Trefoil
Trefoil, the name given to several members of the pea family that have leaves divided into three parts. ( Trefoil means “three leaves.”) Clover is sometimes called trefoil. Other examples include several genera of tick trefoil and the bird's-foot trefoil. The tick trefoils, which are North American wildflowers, are so named because their seed pods stick to clothing. Bird's-foot trefoil is so named because its pods resemble a claw. It is a European wildflower that is grown in the United States as forage.
In art, an ornament or symbol in the form of a stylized three-lobed figure is called a trefoil.
The tick trefoils are of the genus Desmodium. Bird's-foot trefoil is Lotus corniculatus. Trefoils belong to the family Leguminosae.