noun, Psychiatry. 1. an inability to speak, due to a physical defect, conscious refusal, or psychogenic inhibition. Origin of mutism.
1 A new study finds girls are developing breasts earlier than ever before; American boys and girls are entering puberty about five years younger than they did in 1920.
By contrast, the age at which they get their first periods has only declined by a few months and, on average, still occurs, between the ages of 12 and 13. These findings, though still debated by some endocrinologists, have fueled concern that childhood for girls is shrinking, while the duration of puberty is expanding.