Guru (Devanagari गुरु) is a Sanskrit term for "teacher" or "master", especially in Indian religions. The Hindu guru-shishya tradition is the oral tradition or religious doctrine or experiential wisdom transmitted from teacher to student. In the United States, the word guru is a newer term, most often used to describe a teacher from the Hindu tradition.
Take everything you know and get rid of it. Meditate until your bread is toast. Add everything you could never believe. Enjoy!