THY'ROID, a. [Gr. a shield,and form.] Resembling a shield; applied to one of the cartilages of the larynx, so called from its figure, to a gland situated near that cartilage, and to the arteries and veins of the gland.
The thyroid cartilage constitutes the anterior,superior,and largest part of the larynx.
The thyroid gland is situated on the sides and front of the lower part of the larynx, and the upper part of the trachea. It is copiously supplied with blood, but is not known to furnish any secretion. It is the seat of the bronchocele or goiter.