Urticaria is the medical name for the type of skin lesion also known as wheals.
Urticaria is known by many names including hives which is the most common name, "wheals", "weals", and "nettle rash" which is a type of hive or wheal.
Generally, urticaria are rounded or flat-topped elevated lesions caused by flares of swollen skin containing an accumulation of fluid. The medical term for "swollen with an excessive accumulation of fluid" is "edematous", although that word is not used in all medical textbooks.
They usually occur as a result of an allergic reaction and the release of histamine. Although usually transitory, urticaria can be a medical emergency if the lips, eyes, or tongue are affected because considerable swelling can occur.
See also skin conditions and disorders (all on one page). This may interest students of massage, reflexology, holistic treatments of various types, beauty therapies, and other health related courses.
Further information about skin includes the structure of skin (with diagram), an explanation of what dermatology means and includes and textbooks about dermatology.