undecane

from The Collaborative International Dictionary of English v.0.48

Hendecane \Hen"de*cane\, n. [Gr. "e`ndeka eleven.] (Chem.)
   A hydrocarbon, {C11H24}, of the paraffin series; -- so called
   because it has eleven atoms of carbon in each molecule.
   Called also {endecane}, {undecane}.
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Undecane \Un"de*cane\, n. [L. undecim eleven.] (Chem.)
   A liquid hydrocarbon, {C11H24}, of the methane series, found
   in petroleum; -- so called from its containing eleven carbon
   atoms in the molecule.
   [1913 Webster]

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