Pronunciation: (un-rē'zun), [key]
1. inability or unwillingness to think or act rationally, reasonably, or sensibly; irrationality.
2. lack of reason or sanity; madness; confusion; disorder; chaos: a world torn by unreason.
to upset or disrupt the reason or sanity of: The devious plot soon unreasoned the general.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.