Aphthous stomatitis (also termed recurrent aphthous stomatitis, recurring oral aphthae or recurrent aphthous ulceration; from aphtha, "mouth ulcer") is a common condition characterized by the repeated formation of benign and non-contagious mouth ulcers (aphthae) in otherwise healthy individuals. The informal term canker sores is also used, mainly in North America, although this may also refer to any mouth ulcer.