Source : Webster's Revised Unabridged Dictionary (1913)

Hexeikosane \Hex*ei"ko*sane\, n. [Hex- + eikosane.] (chem.)
   A hydrocarbon, {C26H54}, resembling paraffine; -- so called
   because each molecule has twenty-six atoms of carbon.
   [Written also {hexacosane}.]