Dewlap Dewlap A dewlap is a longitudinal flap of skin that hangs beneath the lower jaw or neck of many vertebrates. While the term is usually used in this specific context, it can also be used to include other structures occurring in the same body area with a similar aspect, such as those caused by a double chin or the submandibular vocal sac of a frog. In a more general manner, the term refers to any pendulous mass of skin, such as a fold of loose skin on an elderly person's neck, or the wattle of a bird. Dewlaps can be
Dennie–Morgan fold Dennie–Morgan fold A Dennie–Morgan fold, also known as a Dennie–Morgan line or an infraorbital fold, is a fold or line in the skin below the lower eyelid. It can simply be an ethnic/genetic trait, but was found in one study to occur in 25% of patients with atopic dermatitis. The presence of Dennie–Morgan folds is used as a diagnostic marker for allergy with a sensitivity of 78% and specificity of 76%. Such folds are also common among certain ethnic groups such as Blacks, Tatars, Slavs, Balts, and Finno-Ugric peoples and are not known to be associated with any medical condition