Past

Antonyms of past:
future, futurity, hereafter, present, time to come, instant, prox, rising, inst, immediate, early, in store, existing, incoming, coming, emerging, future day, proximo, forthcoming, latter-day, upcoming, approaching, contemporary, current, extant, ongoing, present-day, prospective, unborn.
Examples of usage:
  1. Oh, let the past be forgotten!
    "The Mystery of a Turkish Bath", E.M. Gollan (AKA Rita).
  2. We know what you've done in the past.
    "Anything You Can Do ...", Gordon Randall Garrett.
  3. Really, this was past a joke.
    "The Heath Hover Mystery", Bertram Mitford.