Source : Webster's Revised Unabridged Dictionary (1913)

Hematoma \Hem`a*to"ma\, n. [NL. See {Hema-}, and {-oma}.] (Med.)
   A circumscribed swelling produced by an effusion of blood
   beneath the skin.

Source : WordNet®

hematoma
     n : a localized swelling filled with blood [syn: {haematoma}]
     [also: {hematomata} (pl)]