- tending to react.
- pertaining to or characterized by reaction.
- Electricity. pertaining to or characterized by reactance.
Origin of reactive
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- readily partaking in chemical reactionssodium is a reactive metal; free radicals are very reactive
- of, concerned with, or having a reactance
- responsive to stimulus
- (of mental illnesses) precipitated by an external causereactive depression
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for over-reactive
Online Etymology Dictionary, © 2010 Douglas Harper
- Tending to be responsive or to react to a stimulus.
- Characterized by reaction.
- Tending to participate readily in chemical reactions.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.