hematoma

n. localized accumulation of blood in the body, swelling due to an accumulation of blood (also haematoma)

A hematoma, or haematoma, is a collection of blood, generally the result of hemorrhage, or, more specifically, internal bleeding. Hematomas exist as bruises (ecchymoses), but can also develop in  organs.It is not to be confused with hemangioma.Hematomas can gradually migrate, as the effused  cells and pigment move in the connective tissue. For example, a patient who injures the base of his thumb might cause a hematoma which will slowly move all through the finger within a week. Gravity is the main determinant of this process.
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Hematoma /he·ma·to·ma/ a localized collection of extravasated blood, usually clotted, in an organ, space, or tissue. [more]Hematoma - Community and Resources

Noun
1. a localized swelling filled with blood
(synonym) haematoma
(hypernym) intumescence, intumescency

n. hematoma, swelling due to an accumulation of blood