Plu·tarch (plōō'tärk') Greek biographer and Neo-Platonist philosopher. He wrote Parallel Lives, a collection of paired biographies of famous Greek and Roman figures that Shakespeare used as source material for his Roman plays. Plu·tarch'an (-tär'kən), Plu·tarch'i·an (-tär'kē-ən) adj.
An ancient Greek biographer noted for his ethical insights. He evaluated the character and conduct of many Greek and Roman rulers in his major work, popularly known as Plutarch's Lives.