Meth"yl*ene (?), n. [F. m'ethylene, from Gr. wine + wood; -- a word coined to correspond to the name wood spirit.] Chem.
A hydrocarbon radical, CH2, not known in the free state, but regarded as an essential residue and component of certain derivatives of methane; as, methylene bromide, CH2Br2; -- formerly called also methene.
Methylene blue Chem., an artificial dyestuff consisting of a complex sulphur derivative of diphenyl amine; -- called also pure blue.
© Webster 1913.