generational

adjective3

1. •
   Of, pertaining to, or changing over generations.

   • The generational shift Mr. Obama once embodied is, in fact, well under way, but it will not change Washington as quickly — or as harmoniously — as a lot of voters once hoped. — 2012
2. •
   (informal) Exceptional; the best/worst of a generation; once-in-a-generation.
3. •
   (informal) Very good/bad (through semantic bleaching or weakening of the above sense).