Source : Webster's Revised Unabridged Dictionary (1913)

Trifolium \Tri*fo"li*um\, n. [L., clover.] (Bot.)
   A genus of leguminous herbs with densely spiked flowers and
   usually trifoliate leaves; trefoil. There are many species,
   all of which are called clover. See {Clover}.

Source : WordNet®

Trifolium
     n : any leguminous plant having leaves divided into three
         leaflets [syn: {genus Trifolium}]