To make someone less sensitive, reactive, or bothered by something, or to reduce the ability to feel or respond emotionally.
From de- (remove) + sensitize (make sensitive or aware) + -ize (make or become). This word developed in psychology and medicine during the 20th century to describe both therapeutic interventions and concerning cultural trends.
Paradoxically, 'desensitization' can be either really good (therapeutic treatment for anxiety) or really bad (watching too much violence might desensitize you to cruelty)—the same word describes both healing and harm.
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