A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z
It's a centuries-old title from India. At that time, a person with a person had to do a lot of living to earn the reputation as a guru. The idea of having a wealth of experience survives to this day.