The Great Plains, the Midwest, the Mississippi Valley and the southern United States are all areas that are vulnerable to tornadoes. They are relatively rare west of the Rockies and are also less frequent in the northeastern states. Tornado Alley is a colloquial term for an area particularly prone to tornadoes.
GCIDE(0.00 / 0 votes)Rate this definition: 1  Limpid(a.) Clear and unambiguous; lucid; easy to understand; -- of speech and writing; as, limpid prose. 2  Limpid(a.) Calm, untroubled, and without worry; serene.
Definition. Pemphigoid is a group of subepidermal, blistering autoimmune diseases that primarily affect the skin, especially the lower abdomen, groin, and flexor surfaces of the extremities. Here, autoantibodies (anti-BPA-2 and anti-BPA-1) are directed against the basal layer of the epidermis and mucosa.