We found 24 dictionaries that define the word reactivity:

General (15 matching dictionaries)

1. reactivity: Merriam-Webster
2. reactivity: Oxford Learner's Dictionaries
3. reactivity: Collins English Dictionary
4. reactivity: Vocabulary.com
5. Reactivity, reactivity: Wordnik
6. reactivity: Wiktionary
7. reactivity: Infoplease Dictionary
8. reactivity: Dictionary.com
9. Reactivity (chemistry), Reactivity (nuclear), Reactivity (psychology), Reactivity: Wikipedia, the Free Encyclopedia
10. reactivity: Rhymezone
11. reactivity: FreeDictionary.org
12. reactivity: Mnemonic Dictionary
13. reactivity: TheFreeDictionary.com

Business (1 matching dictionary)

14. BusinessDictionary.com (No longer online)

Computing (1 matching dictionary)

15. reactivity: Encyclopedia

Medicine (5 matching dictionaries)

16. reactivity: Merriam-Webster Medical Dictionary
17. Dorland's Illustrated Medical Dictionary (No longer online)
18. Reactivity: MedFriendly Glossary
19. online medical dictionary (No longer online)
20. reactivity: Medical dictionary

Science (1 matching dictionary)

21. Reactivity: NRC Glossary of Nuclear Terms --

Tech (1 matching dictionary)

22. Reactivity: Glossary of Air Pollution Terms

(Note: See reactive as well.)

Definitions from Wiktionary (reactivity) ▸ noun:  responsiveness to stimulation ▸ noun:  (chemistry) relative susceptibility to chemical reaction Similar: responsiveness, mechanoresponsiveness, electroresponsiveness, electroresponse, corticoresponsiveness, neuroexcitability, tone, neuroresponse, chemoreflex, vibrotaction, more... Opposite: unresponsiveness, passivity, inactivity Phrases: chemical reactivity, cross reactivity, Reactivity series, cytolytic reactivity, Reactivity controlled compression ignition, more... Adjectives: enhanced, cross, high, emotional, immune, vascular, cardiovascular, low, bronchial, immunological, greater Colors:     red,     orange,     yellow,     lime green,     electric blue, more... ▸ Words similar to reactivity ▸ Usage examples for reactivity ▸ Idioms related to reactivity ▸ Wikipedia articles (New!) ▸ Popular adjectives describing reactivity ▸ Words that often appear near reactivity ▸ Rhymes of reactivity ▸ Invented words related to reactivity