Childlessness is the state of having no children. The word does not say why. Some people cannot have a child; some choose not to; some have not had a child yet, and their life may still change. English uses it in a quiet, serious way — in news, in doctors' rooms, and when people write about family. It is not a rude word, but it can feel heavy, because other people often assume that everyone wants children. Childless is the adjective for the person; childlessness is the noun for the situation. Though actually, some people who chose this life do not like childless, because -less can sound as if something is missing. They may say they are child-free instead. That is a newer way of speaking, and it usually means a choice, not a medical fact.

無子女、沒有小孩。若是自己選擇不生，台灣也會說「丁克」。