Harley Granville-Barker was a renowned English playwright, director, and actor of the late 19th and early 20th centuries. He was known for his innovative approach to theatre, his insightful writing on Shakespeare, and his pioneering efforts to create a more natural acting style. As such, some synonyms for Harley Granville-Barker might include "dramatist," "theatre practitioner," "Shakespeare scholar," "innovator," "director," or "actor." Other possible synonyms might include "pioneer," "trailblazer," "reformer," or "visionary," as he was instrumental in advancing the art of theatre in his time. Regardless of the synonym used, Harley Granville-Barker's contributions to theatre are still celebrated today.