Bruise

The damage or breakage of soft tissue or bone without breaking the skin, often leading to discolouration of the area to black, blue, and purple if you're really lucky, fading to a green/yellow and brown. It's inflicted by a blow or excessive pressure. A good remedy for bruises is a salve made out of comfrey.

Bruises can also simply be a breakage of plant tissue, such as a light grinding or folding of leaves, or applying pressure to the tissue of a fruit.