Gynecomastia, or gynaecomastia, pronounce /ˌgaɪnəkoʊˈmæstiə/ is the development of abnormally large mammary glands in males resulting in breast enlargement, which can sometimes cause secretion of milk. The term comes from the Greek gyne (oblique stem gynaik-) meaning "woman" and mastos meaning "breast". The condition can occur physiologically in neonates (due to female hormones from the mother), in adolescents, and in the elderly. In adolescent boys the condition is often a source of distress, but for the large majority of boys whose pubertal gynecomastia is not due to obesity, the breast development shrinks or disappears within a couple of years . The causes of common gynecomastia remain uncertain, although it has generally been attributed to an imbalance of sex hormones or the tissue responsiveness to them; a root cause is rarely determined for individual cases. Breast prominence can result from hypertrophy of breast tissue, chest adipose tissue and skin, and is typically a combination. Breast prominence due solely to excessive adipose is often termed pseudogynecomastia or sometimes lipomastia.