What is defined as excess scar tissue formed after an injury?

The term for excess scar tissue formed after an injury is defined as a keloid. A keloid is characterized by an overgrowth of fibrous tissue that extends beyond the boundaries of the original wound. This type of scar can be raised, firm, and sometimes discolored, appearing as a thick, irregular patch on the skin. Keloids often occur in response to skin injury or surgical incisions, where the body's healing processes lead to an excessive production of collagen in the area, resulting in the formation of this type of scar.

In contrast, a standard scar refers to the normal healing process where the body repairs damaged tissue but does not necessarily involve the same degree of excess tissue formation seen in keloids. A bruise is a type of contusion resulting from blood vessels breaking beneath the skin, leading to discoloration, but it is not a type of scar. A lesion is a general term that refers to any abnormal tissue or area of damage, which can include various forms of injury or disease but is not specifically indicative of scar tissue formation. Thus, keloid is the precise term for this condition of excessive scar tissue.