A journey through a particular building, estate, country, etc.

“On our last holiday to Spain we took a tour of the wine-growing regions.”

A guided visit to a particular place, or virtual place.

“On the company's website, you can take a virtual tour of the headquarters.”

A journey through a given list of places, such as by an entertainer performing concerts.

“Metallica's tour of Europe”

To make a journey

“The Rolling Stones were still touring when they were in their seventies.”

To make a circuit of a place

“The circuses have been touring Europe for the last few weeks.”