Added 10 October 2026 reactivity /rɪˈakˈtɪvɪti/ noun Categories: Mind & IdeasDescribing WordsUncommon Words noun ! Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about reactivity at Wordnik → Where our words come from → responsiveness to stimulation relative susceptibility to chemical reaction Related Words: responsivenessreactionresourcefulnessresponseadaptabilitybehaviorsensitivityreagentreactantcross-reactivityactivityvolatility Back to today's word