·noun A charge representing the clover leaf.
II. Trefoil ·noun An ornamental foliation consisting of three divisions, or foils.
III. Trefoil ·noun Any plant of the genus Trifolium, which includes the white clover, red clover, ·etc.;
— less properly, applied also to the nonesuch, or black medic. ·see Clover, and Medic.