The Collaborative International Dictionary of English v.0.48:

Steatoma \Ste`a*to"ma\ (-t[=o]"m[.a]), n. [L., fr. Gr.
   stea`twma, fr. steatoy^n to turn into tallow or suet, fr.
   ste`ar, -atos, fat, suet.] (Med.)
   A cyst containing matter like suet.
   [1913 Webster]