‖n. [ NL. See Hypo, and derma. ] 1. (Bot.) A layer of tissue beneath the epidermis in plants, and performing the physiological function of strengthening the epidermal tissue. In phanerogamous plants it is developed as collenchyma. [ 1913 Webster ]
2. (Zool.) An inner cellular layer which lies beneath the chitinous cuticle of arthropods, annelids, and some other invertebrates. [ 1913 Webster ]