The Collaborative International Dictionary of English v.0.48:
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. [1913 Webster]WordNet (r) 3.0 (2006):
myxoma n 1: a benign tumor of connective tissue containing jellylike material