From Longman Dictionary of Contemporary Englishmammary glandˈmammary ˌgland noun [countable] technicalHBHHBA the part of a woman’s breast that produces milk, or a similar part of a female animal
Examples from the Corpus
mammary gland• Thus elm trees clone themselves to form entire copses, and we cloned Dolly from cultured mammary gland cells.• Thus the beta-lactoglobulin gene is expressed only in the mammary gland, and only during lactation. 