underreact definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
to react with less emotion, force, or intensity than is appropriate or expected
underreact definition by American Heritage Dictionary
intransitive verb un·der·re·act·ed, un·der·re·act·ing, un·der·re·acts
To react with insufficient enthusiasm, force, or emphasis.
- unˌder·re·acˈtion noun