Etymology

Noun

1. A condition of hypersensitivity to a substance (an allergen) considered harmless to most people. Exposure (consumption, inhalation, physical contact, etc) to such substances causes the body to undergo a reaction, often resulting in symptoms such as difficulty breathing and/or swellings/rashes of the skin.
2. Altered susceptibility to a first treatment as exhibited in reaction to a subsequent one.
3. An antipathy, as toward a person or activity.

   He is allergic to reality TV.