Dictionary:

ecchymosis

  (ĕk'ĭ-mō'sĭs)

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The passage of blood from ruptured blood vessels into subcutaneous tissue, marked by a purple discoloration of the skin.

[New Latin, from Greek ekkhumōsis, extravasation, from ekkhumousthai, to extravasate : ek-, out; see ecto– + khumos, juice.]

A discoloration of mucous membranes caused by a diffuse extravasation of blood. Frequently called a bruise.

Ecchymosis. (Regezi/Sciubba/Jordan, 2003)

A bruise caused by an injury or spontaneous diffusion of blood from blood vessels, characterized by a red or bluish-black discoloration just under the skin. An ecchymosis under the conjunctiva in the eye (a ‘bloodshot’ eye) may result from chemical or physical irritation.

Pl. ecchymoses [Gr.] a hemorrhagic spot, larger than a petechia, in the skin or mucous membrane, forming a nonelevated, rounded or irregular, blue or purplish patch.