• A bump of bone or tissue that forms at the big toe joint, causing inflammation and considerable pain.
  Harvard Dictionary of Health Terms
  Harvard Medical Publishing, 2011
• Abnormal swelling of the inner aspect of the first metatarsal head affecting the first METATARSOPHALANGEAL JOINT.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2025
• Bunion is a prominence of the medial portion of the head of the 1st metatarsal bone. The cause is often variations in position of the 1st metatarsal bone or great toe, such as lateral angulation of the great toe (hallux valgus). Secondary osteoarthritis and spur formation are common. Symptoms may include pain and redness, bursitis medial...
  Merck Manuals
  Merck & Co., Inc., 2025
• Hallux valgus (HV), with its accompanying bunion, is a common deformity of the forefoot involving the first ray, with first phalanx abduction and pronation, and first metatarsal adduction, pronation, and elevation, along with capsular and ligamentous derangement (see images below). Understanding and character...
  Medscape
  WebMD, 2025
• A bunion is a bony bump that forms on the joint at the base of your big toe. It occurs when some of the bones in the front part of your foot move out of place. This causes the tip of your big toe to get pulled toward the smaller toes and forces the joint at the base of your big toe to stick out. The skin over the bunion might be red and...
  Mayo Clinic
  Mayo Foundation for Medical Education and Research, 2025
• Bunion, type of bursitis that appears as a bulge covered by thickened skin occurring at the base of the big toe, where friction against the side of the shoe takes place. The protuberance is due to a swelling of the bursa mucosa, a closed sac filled with a clear, lubricating fluid. The bunion...
  Encyclopedia Britannica
  Encyclopedia Britannica, Inc., 2025