tetramethylene

Tet`ra*meth"yl*ene, n. Etym: [Tetra- + methylene.] (Chem.) (a) A hypothetical hydrocarbon, C4H8, analogous to trimethylene, and regarded as the base of well-known series or derivatives. (b) Sometimes, an isomeric radical used to designate certain compounds which are really related to butylene.

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