Final answer:
A contusion is a localized soft tissue injury characterized by swelling and bruising. It occurs when blood vessels near the skin's surface are damaged, causing blood to leak into the surrounding tissue.
Step-by-step explanation:
A localized soft tissue injury characterized by swelling and bruising is known as a contusion. It occurs when blood vessels near the skin's surface are damaged, causing blood to leak into the surrounding tissue. This results in the appearance of bruising and swelling.