1. to make someone less sensitive to or less affected by something, especially through repeated exposure
Usage: British spelling (U.S. equivalent: desensitizes); third-person singular present tense
2. to reduce or eliminate an allergic or phobic response through gradual exposure to the triggering stimulus
Usage: psychology and medical contexts

Examples

• Watching too much violence on television desensitises children to real suffering.
• The therapist desensitises her patients to their phobias through controlled exposure.
• Repeated exposure to the alarm sound desensitises people to its urgency.
• Social media desensitises users to disturbing content over time.
• The treatment desensitises allergic reactions by introducing small amounts of the allergen.
• Constant notifications desensitise us to important messages.