methylene

n. hydrocarbon radical that is regarded as an essential residue and component of certain derivatives of methane (Chemistry)

In chemistry, methylene is a divalent functional group CH2 derived formally from methane. The name "methylene" is used for the following:−CH2− group (bound by two single bonds) present e.g. in dichloromethane (alternative name is methylene chloride).=CH2 group (bound by one double bond), present e.g. in methylenecyclopropene.:CH2 is a carbene known as methylene, carbenes are highly reactive organic molecules with a divalent carbon atom with only six valence electrons.
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Methylene /meth·y·lene/ the bivalent hydrocarbon radical —CH2— or CH2dbond. meth·yl·ene n. A bivalent hydrocarbon radical, CH 2, that is a component [more]Methylene - Community and Resources

Noun
1. the bivalent radical CH2 derived from methane
(synonym) methylene group, methylene radical
(hypernym) group, radical, chemical group

n. methylene, hydrocarbon radical that is regarded as an essential residue and component of certain derivatives of methane (Chemistry)