Definition of "guru"

When the gooroo arrives at the house of a disciple, the whole family prostrate themselves at his feet, and the spiritual guide puts his right foot on the heads of the prostrate family.

1817, William Ward, History, Literature and Religion of the Hindoos, volume II

Traditionally, a guru is a spiritual teacher who guides a student on the road to Enlightenment, or finding God.

2010 May 10, “Madonna is my guru”, in Alan Rusbridger, editor, The Guardian‎, London: Guardian News & Media, archived from the original on 2022-09-24

Many oenophiles rely on the ratings and recommendations of wine guru Robert Parker when selecting the perfect bottle.

2004 October 18, “Vintage technology”, in Time

OPCA gurus are modern legal alchemists. They promise gold, but their methods are principally intended to impress the gullible, or those who wish to use this drivel to abuse the court system. Any lack of legal success by the OPCA litigant is, of course, portrayed as a consequence of the customer’s failure to properly understand and apply the guru's special knowledge.

2012, John D. Rooke (Court of Queen’s Bench of Alberta), “Meads v. Meads, 2012 ABQB 571”, in CanLII‎