Adenoid (noun)

1. A mass of lymphoid tissue located at the back of the nasal cavity.
2. A small bump located behind the nose, above the roof of the mouth.

Origin:

From the greek word aden, meaning "gland".

Examples:

1. The adenoid can become swollen and cause difficulty in breathing.
2. The doctor recommended removal of the patient's adenoid.
3. The patient's adenoids were swollen, which was causing difficulty in breathing.
4. Adenoid surgery is usually performed on children.
5. The adenoid is a part of the body's immune system.