Tonsillitis refers to inflammation of the pharyngeal tonsils.
Inflammation may involve other areas of the back of the throat including the adenoids and the lingual tonsils. The tonsils are lymph nodes, or oval-shaped masses of lymph gland tissue, located on both sides of the throat. An infection of the tonsils is called tonsillitis.
There are several variations of tonsillitis: acute, recurrent, and chronic tonsillitis and peritonsillar abscess. This swelling is usually caused by either a viral or bacterial infection. Tonsillitis is the name given to swollen, red, and tender tonsils.