Mammography is a medical test: a machine takes X-ray pictures of a woman’s breasts to look for early signs of cancer. Doctors often use it as a check even when she feels fine, because some changes are too small to feel with the hand. The test itself is mammography; the picture it makes is usually called a mammogram — two names people mix up. It can feel uncomfortable, because the breast is pressed flat for a few seconds so the picture is clear, though actually it is quick. It is a clinic and hospital word, not a word for ordinary chat. In many countries women over a certain age are asked to have it every few years.