D defs.my
Entry 3 senses Webster, 1913

Trefoil

· Tre·foil · IPA /ˈtɹɛ.fɔɪl/
01 n. Any plant of the genus Trifolium, which includes the white clover, red clover, etc.; -- less properly, applied also to the nonesuch, or bla…
  1. 1.
    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.(Bot.) See: Clover, Medic
  2. 2.
    An ornamental foliation consisting of three divisions, or foils.(Arch.)
  3. 3.
    A charge representing the clover leaf.(Her.)