Folium :: Folium (n.) A leaf, esp. a thin leaf or plate..
Folium :: Folium (n.) A curve of the third order, consisting of two infinite branches, which have a common asymptote. The curve has a double point, and a leaf-shaped loop; whence the name. Its equation is x3 + y3 = axy..
Trifolium :: Trifolium (n.) 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..