word
Sanskrit

Guru

lit. “heavy, weighty”

A spiritual teacher in Hinduism and Sikhism — and, in English, an acknowledged expert in any field.

Origin

In the Indian traditions, a guru is far more than a teacher: the figure who transmits wisdom directly, often through a deep one-to-one relationship that may last a lifetime. Sikhism is named for and built around its ten human Gurus and the scripture treated as their successor, the Guru Granth Sahib. The word entered English in the early 19th century via colonial India.

Modern usage

Now ordinary English for any acknowledged expert — 'marketing guru', 'productivity guru', 'tech guru'. Often faintly mocking, hinting that the person has a cult-of-personality vibe. The original religious sense survives mainly in writing about Hinduism, Sikhism, and yoga lineages.

In the wild

He's the productivity guru everyone's quoting on LinkedIn.— common usage

Tags

teacher
hinduism
expertise