Tonsils, Or Amygdalae, two glandular organs, of an almond shape, with the larger end upward, situated on each side of the fauces, between the anterior and posterior pillars of the soft palate, and easily brought into view by opening the mouth. They are composed of a collection of mucous follicles, which open through 12 or 15 orifices on the inner side of each tonsil. These follicles are lined with a continuation of the mucous membrane of the pharynx, and have a structure similar to that of Peyer's glands in the small intestine. They secrete mucus which goes to make up the mixed mass of saliva, or to lubricate the fauces during the act of deglutition, the pressure of the food and the constriction of the pharynx forcing the contents from the organs. They are supplied with blood from the facial, inferior pharyngeal, and internal maxillary arteries, and with nerves from the fifth and glossopharyngeal. The veins terminate in the tonsillar plexus on the outer side of the tonsil. These organs vary in size in different individuals, being notably larger in persons of scrofulous constitution.

They are liable to acute inflammation, involving great enlargement and suppuration; an affection called tonsillitis or cynanche tonsillaris, and popularly quinsy.