A guru is someone recognized as an expert or authority who guides and teaches others in a particular field. The word comes from ancient India, where a guru was a spiritual teacher who passed down wisdom and knowledge to dedicated students. Today, we use it much more broadly.

When someone becomes known as a tech guru, people seek their advice about computers and software. A fitness guru might have thousands of followers who trust their workout routines and nutrition tips. Your math teacher might jokingly call herself a multiplication guru when helping students master their times tables.

The word carries a sense of deep knowledge combined with the ability to explain things clearly. A guru has expertise and can help others understand and improve through clear teaching. However, people sometimes use the term loosely or even sarcastically. If your friend always knows the best routes to avoid traffic, you might tease them by calling them your navigation guru.

Just because someone calls themselves a guru doesn't mean they truly are one. Real expertise takes years of study and practice to develop. The title means more when others give it to you out of respect and recognition than when you claim it for yourself.