ecchymosis

from WordNet (r) 3.0 (2006)

ecchymosis
    n 1: the purple or black-and-blue area resulting from a bruise
    2: the escape of blood from ruptured blood vessels into the
       surrounding tissue to form a purple or black-and-blue spot on
       the skin

from The Collaborative International Dictionary of English v.0.48

Ecchymosis \Ec`chy*mo"sis\, n.; pl. {Ecchymoses}. [NL., fr. Gr.
   ?, fr. ? to extravasate; 'ek out of + ? to pour.] (Med.)
   A livid or black and blue spot, produced by the extravasation
   or effusion of blood into the areolar tissue from a
   contusion.
   [1913 Webster]

from Bouvier's Law Dictionary, Revised 6th Ed (1856)

ECCHYMOSIS, med. jur. Blackness. It is an extravasation of blood by rupture 
of capillary vessels, and hence it follows contusion; but it may exist, as 
in cases of scurvy, and other morbid conditions, without the latter. Ryan's 
Med. Jur. 172.

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