- noun a form of carbon made up of up to 500 carbon atoms arranged in a sphere or tube
- An allotropic form of carbon arranged in a manner that forms a hollow sphere, cylinder, or the like. These may range from as few as 20 carbon atoms, to several hundred, always in specific multiples of atoms. The most common and stable found to date is buckminsterfullerene, with 60 atoms. Fullerenes are extremely strong and lightweight, are capable of enclosing other atoms, and have applications in various areas, including electronics, optics, superconduction, and medicine.