This is the 16290th most frequent Russian word.
регби
Rugby.
Here, 'регби' is used as a noun indicating the sport itself.
Я играю в регби каждую субботу.
I play rugby every Saturday.
In this sentence, 'регби' defines the subject of the sentence, referring to the sport abstractly.
Регби — это увлекательная командная игра.
Rugby is an exciting team game.
'регби' is used in a possessive context to indicate the type of ball purchased.