The definition of a guru is a spiritual leader, or is a widely respected expert.
(noun)See guru in Webster's New World College Dictionary
noun
Origin: Hindi guru < Sans guruḥ, venerable, orig. heavy < IE *gweru- < base *gwer- > grave
See guru in American Heritage Dictionary 4
noun pl. gu·rus
Origin:
Origin: Hindi guru
Origin: , from Sanskrit guruḥ
Origin: , from guru-, heavy; see gwerə-1 in Indo-European roots
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