NCIt definition : The pigmented protuberance on the surface of the breast through which milk is drawn
from the breast.;
Alternative definition : NCI-GLOSS: In anatomy, the small raised area in the center of the breast through which
milk can flow to the outside.; CDISC: The protuberance in the skin where the ducts of the mammary gland open.; UBERON: Projection of skin containing the outlets for 15-20 lactiferous ducts arranged
cylindrically around the tip.;