Guru (noun)

1. A person who is regarded as an expert or leader in a particular field or area of expertise.
2. A spiritual guide or teacher, especially in Hinduism and Buddhism.

Origin:

From hindi and punjabi guru ("teacher, spiritual guide"), from sanskrit guru ("venerable, weighty, heavy"), from proto-indo-iranian *guru- ("heavy, weighty"), from proto-indo-european *gʰer- ("heav.y")

Examples:

1. He is a guru in the field of computer science.
2. She is a guru in the field of yoga.
3. The guru taught his students the way to enlightenment.
4. The guru was respected by all his followers.
5. He followed the teachings of his guru.