Ponderous

a.
  1. Very heavy; weighty; as, a ponderous shield; a ponderous load; the ponderous elephant.
  2. Important; momentous; forcible.
  3. Heavy; dull; wanting; lightless or spirit; as, a ponderous style; a ponderous joke.
    4. Ponderous spar (Min.),
    heavy spar, or barytes. See Barite.