A "matron" is a term used to describe a woman who is mature, usually married, and has an authoritative or responsible role, especially in a professional or caretaker position. Full definition
I wore this dress for my sister's wedding as matron of honor. (renttherunway.com)
Fredericks & Freiser (A23) for example will show only paintings by Thomas Trosch, whose exuberant paintings of society matrons the artist rarely allows to be exhibited. (frieze.com)
Miscegenated Family Album (Ceremonial Occasions I), L: Devonia as Matron of Honor; R: Nefertiti performing a lustration, 1980/1994 (alexandergray.com)