Great Russia, also known as Greater Russia or Grand Russia, refers to the concept of a larger and more powerful version of Russia that includes territories beyond its current borders.
Imagine you have a toy car that you really like to play with. You might imagine that it would be even more fun if you had more cars to play with, or if the cars were bigger and stronger. That's kind of like what some people think about Russia. They wish that Russia was bigger and more powerful than it already is.
For example, some people think that Russia should include the territories of neighboring countries, like Ukraine, Belarus, and Kazakhstan. They believe that these lands should belong to Russia because they have historical and cultural connections to Russia.
However, not everyone agrees with the idea of Great Russia. Some people think that it is wrong to take over other countries, and that it would only lead to more conflict and problems.
In any case, the concept of Great Russia is a controversial and complex issue that has been debated for many years.