Definities van hives op het Internet in het Engels:
urtication: an itchy skin eruption characterized by weals with pale interiors and well-defined red margins; usually the result of an allergic response to insect bites or food or drugs
wordnet.princeton.edu/perl/webwn
Urticaria or hives is a relatively common form of allergic reaction that causes raised red skin welts that range upwards from 5 mm (about a 1/4 inch) in diameter, itch severely, and often have a pale border. Urticaria is caused by direct contact with an allergenic substance (generally a plant, such as poison ivy), or an immune response to food or some other allergen. Hives can also be caused by stress. Urticaria is also known as nettle rash or uredo.
en.wikipedia.org/wiki/Hives