Cutis laxa: A dermatologic condition characterized by unusually loose skin which may hang in pendulous folds. Cutis laxa is usually a genetic disorder. A mild autosomal dominant form can be caused by mutation in the elastin gene (the ELN gene). Mutations in the gene encoding fibulin-5 (FBLN5) can cause either autosomal dominant or a more severe autosomal recessive form of cutis laxa. There is also an X-linked type of cutis laxa.