doyen
Pronunciation: 'doi-&n, -"(y)en; 'dwä-"yan(n)
Function: noun
Etymology: French, from Late Latin decanus dean -- more at DEAN
1 a : the senior member of a body or group
b : a person considered to be knowledgeable or uniquely skilled as a result of long experience in some field of endeavor
2 : the oldest example of a category

doyenne
Pronunciation: doi-'(y)en, dwä-'yen
Function: noun
Etymology: French, feminine of doyen: a woman who is a doyen

(from ST)