reactivity reactiveness • reactological · · · Info · Definitions · Synonyms · Characters · · reactivity · · Text Latin · · Script 10 · · Length Definitions · · · (noun) responsive to stimulation. Synonyms: responsiveness. · · Noun Definition 1 (noun) ready susceptibility to chemical change. · · Noun Definition 2 Synonyms · · · responsiveness · · Synonym 1 Characters · · a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 r latin small letter r U+0072 t latin small letter t U+0074 v latin small letter v U+0076 y latin small letter y U+0079