n. A small circumscribed elevation on the skin, usually with an uneven papillary surface and a broad base, caused by a localized overgrowth of the papillæ and epidermis; verruca; hence, a similar natural excrescence of the skin.n. In farriery, a spongy excrescence on the pastern of the horse.n. In botany, a firm glan dular or gland-like excrescence on the surface of a plant.n. In entomology, a small obtuse, rounded, or flattened elevation of a surface, often of a distinct color from the rest of the part: used principally in describing larvæ.