Lingual tonsil

The lingual tonsils are aggregates of lymphoid tissue located at the base of the tongue, posterior to the circumvallate papillae. They are part of Waldeyer's ring, which is a ring of lymphoid tissue that includes the palatine tonsils, pharyngeal tonsils (adenoids), and tubal tonsils. The lingual tonsils are covered by nonkeratinized epithelium and contain crypts formed by invaginations of the overlying epithelium, which are involved in immune responses to ingested or inhaled antigens