If I could explain mundane time, I would understand it and not be searching for what it is! I do appreciate your question tho. Time is 'marked'- roman calendar, days of the year/month/week but it's a man-made system of counting/of marking time. That time itself is relative and is made up of individual experiences and that group think/mass vibration can change time to match/change outcomes or change time and affect the future of time/experience.
And if that makes sense to you, then you are well on your way to understanding more than I know about it! VERY difficult subject matter, imo.
Def: of or relating to this world or earth as contrasted with heaven; worldly; earthly: mundane affairs.
of or relating to the world, universe, or earth. Time is/is not linear. Time is what we make it?