noun, plural: ecchymoses
(1) An effusion of blood underneath the skin due to ruptured blood vessel.
(2) A haemorrhagic spot in the skin (or mucous membrane) that is flat, rounded or irregular, and bluish or purplish in colour, caused by extravasation of blood.
Ecchymosis is larger in size than a petechia and has a more diffuse border than purpura. It is caused by an escape of blood from the damaged blood vessel into the tissues.
Word origin: Word origin: Greek ek + chymos (juice) + osis
Related forms: ecchymose (verb), ecchymotic (adjective)
Related term: Orbital ecchymoses