Synonyms: Flare

Wheal definition

An enlarged, hive-like zone of puffiness on the skin, often due to an allergic reaction. (Alcamo’s Fundamentals of Microbiology)

A welt; marked, slightly red, usually itchy bumps on the skin that change in size and shape as they spread. It is surrounded by a red patch (the flare). The reaction is triggered by cutaneous contact or intradermal injection of allergens in sensitive individuals. (Foundation in Microbiology by Talaro and Chess)