ful·ler·ene 
(f
l
ə-r
ēn
′)
n. An allotrope of carbon composed of any of various cagelike molecules that consist only of an even number of carbon atoms, are often spherical in shape, and are composed of hexagonal and pentagonal groups of atoms.
[After Richard Buckminster Fuller (from the resemblance of their configurations to his geodesic domes) + -ENE.]