thyroid

(thi’ roid) [Gr. θυρεοειδής; θυρεὸς shield + eldos form]. Resembling a shield; scutiform. 2. A large reddish, ductle gland in front of and on either side of the trachea, and usually consist - ing of two lateral lobes and a connecting isthmus. The thyroid is inclosed in a covering of areolar ti ue, and is made up of numerous closed follicles surrounded by a vascular network and containing colloid matter. It is probably a hematopoietic organ, and performs various functions of the highest importance in the economy of the body. The colloid matter of the thyroid is composed of a protein and a non-protein constituent, together with phosphorus and iodin, a nucleo-albumin, and certain extractive compounds. Shcep thyroids are used in the treatment of certain diseases. Called also t. body, t. gland. See thyroid therapy, under thera py; also thyraden and thyroid in, to do thy rin, etc. acce ory t., an exclave or detached portion of the thyroid occasionally present at the base of the tongue: sometimes more than one is present. It is quite distinct from the parathyroids. t. body, t. gland, the thyroid. t. cartilage. ‘se under cartilage. t. extract, one of the therapeutic preparations of the thyroid of animals.