Guru is a Sanskrit and pan-Indian word denoting a spiritual master or teacher. It implies an initiatory relation between master and disciple. The Guru thus is a link in a supposedly unbroken chain of oral tradition and ascetic regimen to which the student is added as another link in the chain.

In Sikh usage, "guru" signifies one of the 10 saintly leaders of the Sikh community, from Nanak (1469-1539), founder of the Sikh religion, to Govind Singh (1666-1708), who organized the Sikhs into a powerful military force. Since Govind's death the Granth, or scriptures has received honor as the Guru.

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