ecchymosis

noun

1. (countable, uncountable)A skin discoloration caused by bleeding underneath the skin, especially one that is remote from a site of trauma or caused by a non-traumatic process (such as neoplasia).

   “A diseased condition of the skin has often been mistaken for stigmatic marks. Such, for instance, is ecchymosis, a discoloration of the skin due to the extravasation of subcutaneous blood.”