doyenne

A female doyen.

The senior or eldest female member of a group, especially one who is most or highly respected.

Helen Thomas is frequently referred to as "the doyenne of the White House press corps".

The French, who celebrated her as the doyenne of humanity, had their own theories about why she lived so long, noting that she used to eat more than two pounds of chocolate a week and treat her skin with olive oil, rode a bicycle until she was 100, and only quit smoking five years ago.

A woman who is highly experienced and knowledgeable in a particular field, subject, or line of work; expert.