Source : Webster's Revised Unabridged Dictionary (1913)

Myxoma \Myx*o"ma\, n.; pl. {Myxomata}. [NL., fr. Gr. ? mucus +
   -oma.] (Med.)
   A tumor made up of a gelatinous tissue resembling that found
   in the umbilical cord.

Source : WordNet®

myxoma
     n : a benign tumor of connective tissue containing jellylike
         material
     [also: {myxomata} (pl)]