Tetter \Tet"ter\, n. [OE. teter, AS. teter, tetr; akin to G. zitter, zittermal, OHG. zittaroch, Skr. dadru, dadruka, a sort of skin disease. [root]63, 240.] (Med.) A vesicular disease of the skin; herpes. See {Herpes}. {Honeycomb tetter} (Med.), favus. {Moist tetter} (Med.), eczema. {Scaly tetter} (Med.), psoriasis. {Tetter berry} (Bot.), the white bryony.