ma ‧ tron /ˈmeɪtrən/ BrE AmE noun [countable]
[ Date: 1300-1400 ; Language: French ; Origin: matrone , from Latin matrona , from mater 'mother' ]
1 . literary an older married woman
2 . British English old-fashioned a nurse who is in charge of the other nurses in a hospital
3 . British English a woman who works as a nurse in a private school
4 . American English a woman who is in charge of women and children in a school or prison