"To redefine the genre" means to change or revolutionize the way a particular category or style of something, such as music, movies, or literature, is typically understood or presented. Full definition
While it's not a title that will redefine the genre of beat - em - ups, it can be a relatively good time given you can grab some friends to play with. (metacritic.com)
It helped redefine a genre, it established the ideal of a prosperous user - generating community and it would influence some of the biggest franchises in modern videogame history. (gamestm.co.uk)
Every so often a game comes along that tries to redefine a genre by introducing new elements. (xbox-360.co.za)