puberty: [14] Latin pūber denoted ‘adult’, and hence, by implication, ‘covered in hair’. Both strands of meaning have followed the word into English: ‘adulthood’ by way of the derivative pūbertās, source of English puberty, and ‘hairiness’ in pubescent [17], which means ‘downy’ as well as ‘having reached puberty’. And the two are combined in pubic ‘relating to the region of the groin where hair begins to grow at puberty’ [19]. [puberty etymology, puberty origin, 英语词源]