any of a group of younger people seeking to take control of an organization, party, country, etc. from an entrenched, usually conservative, group of older people
See Young Turk in American Heritage Dictionary 4
noun
A member of a Turkish reformist and nationalist political party active in the early 20th century.
also young Turk
a. A young progressive or insurgent member of an institution, movement, or political party.
b. A young person who rebels against authority or societal expectations.