Mastitis

Mastitis is the inflammation of the mammalian breast. It is called puerperal mastitis when it occurs to breastfeeding mothers and non-puerperal otherwise. Mastitis can rarely occur in men. Inflammatory breast cancer has symptoms very similar to mastitis and must be ruled out.

Chronic cystic mastitis, also called fibrocystic disease, a condition rather than a disease, is characterized by noncancerous lumps in the breast.

American slang: here mastitis usually refers to puerperal (occurring to breastfeeding mothers) mastitis with symptoms of systemic infection. Lighter cases of puerperal mastitis are often called breast engorgement.

Names for non-puerperal mastitis are not used very consistently and include Mastitis, Subareolar Abscess, Duct Ectasia, Periductal Inflammation, Zuska's Disease and others.

In this wikipedia article mastitis is used in the original sense of the definition as inflammation of the breast with additional qualifiers where appropriate.