Definition of "affective disorder" []

• A mental disorder characterized by a consistent, pervasive alteration in mood, and affecting thoughts, emotions, and behaviors. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Light therapy has been used previously for people with significant seasonal affective disorder as well as nonseasonal depression."
• "Seasonal affective disorder is well known to people who live at northern latitudes."