A mammogram is an X-ray picture of a woman’s breasts, taken to look for early signs of cancer — tiny changes you cannot feel with a hand. Strictly it is the picture, though actually people also say “I’m going for a mammogram” to mean the whole visit: the machine, the squeeze, the wait. It is a health-care word, used by doctors and by ordinary adults talking about screening; it is not slang and not a children’s word. Men can have breast problems too, but the routine public screening people mean by mammogram is almost always for women, from middle age on, depending on the country’s rules.