guru bramha guru vishnu guru devo maheshwara
guru sakshat parabramha tasmayee sree guruve namaha
The true meaning of Guru is "one who dispels darkness of ignorance". "Gu" means "darkness of ignorance" and "Ru" means "one who removes". Guru resembles the trinity Brahma, Vishnu and Shiva. Brahma is creator. Guru creates or inculcates knowledge in the minds of the students. Guru is Vishnu. Lord Vishnu maintains the creation. Similarly Guru helps in keeping up the knowledge. Guru is like Shiva. Shiva is the destroyer. Guru destroys or gets rid of the ignorance from the students' minds.
Another meaning of the word Guru is "one who is beyond attributes and forms". Gu stands forGunaatheetha - one who transcends the three Gunas (Satva, Rajas and Thamas); Ru stands forRupavarjitha - one who is formless. The One who is beyond all attributes and forms is none other than the Supreme Self (the Brahmam) who is resident within each of us. Only God can be regarded as One who is beyond attributes and forms.