In plants, a layer of waxy substance on the outer surface of epidermal cell walls In animals, the outermost layer of many invertebrates
(1) a waxy covering on the surface of stems and leaves that acts as an adaptation to prevent desiccation in terrestrial plants (2) the exoskeleton of an arthropod, consisting of layers of protein and chitin that are variously modified for different functions
the continuous layer of cutin secreted by the epidermis, it prevents plant desiccation by being impervious to water and gas exchange and covers the aerial parts of the plant body, broken only by stomata and lenticels