urticaria (ur-tik-a're-ah)

Hives, nettle rash; an acute or chronic affection of the skin characterized by an eruption of red, elevated, rounded efflorescences of irregular shape and size, which at a certain stage of their development appear: blanched in the center and erythematous at the periphery, being then commonly known as wheals. The eruption is attended with intense itching. It is usually transitory, though sometimes disposed to recur, u. pigmentosa. Syn.: xanthelasmoidea. A rare affection characterized by the development of wheals which are followed by peculiar persistent pigmented macules, papules or nodules. The following varieties are cla ified by dermatologists, u. acuta, u. bullosa, u. chronic a, u. fact it i a, u. febrilis, u. gigans, u. hemorrhagic a, u. papulosa, u. perstans, u. pigmentosa (see above), u. subcutanea, u. sub serosa. [Lat., urtica, a nettle.]