Dictionary.net

Under this term Mr. Birkett includes tumours of the mammae, which contain structures similar to, if not identical with, the normal secreting tissue of the gland, and more especially the cysto-sarcoma, and chronic mammary tumours of surgical anthors.

A cystic, adenomatous tumor.

A rare form of tumor of the breast, consisting of a cyst or cysts of the ducts or sinuses containing adenomatous growths apparently springing from the walls. [Gr.]