Usage: usually capitalized G
: a system of nomenclature adopted by an international congress of organic chemists in Geneva in 1892 and later modified and added to by the International Union of Pure and Applied Chemistry resulting in a systemic nomenclature in which names of compounds are formed from those of parent hydrocarbons with use of prefixes and suffixs (as 2-methyl-butane for isopentane, butanone for methyl ethyl ketone, hexanoic acid for caproic acid)
Useful english dictionary. 2012.