Trefoil(n.)
- 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.
Trefoil(n.)
- An ornamental foliation consisting of three divisions, or foils.
Trefoil(n.)
- A charge representing the clover leaf.