Concentrated

Antonyms of concentrated:
distributed, unconcentrated, uncondensed, unsaturated, sparse, divided, shared out, far-flung, shared, thin, parceled out, separated, spread, mild, divided up, diffused, unfocussed, diffuse, dispersed, low-density, rationed, dealt out, dilute, broken, encyclical, diluted, unfocused, meted out, straggly, dispensed, doled out, apportioned, spaced, widespread, splashed, scattered, fanned, spread-out, watered-down, watery, delicate, light, thinned, weak, weakened, deficient, fragmental, fragmentary, halfway, incomplete, partial.
Examples of usage:
  1. Lorraine stood frowning with concentrated thought.
    "The Head Girl at the Gables", Angela Brazil.
  2. But now no one observed him; while he, gathered up and concentrated, like some old wolf upon a trail, followed every movement of the party entering the Gaddesden car.
    "Lady Merton, Colonist", Mrs. Humphry Ward.
  3. No; even such a resolution could not account for her remarkable expression of concentrated will.
    "The Chief Legatee", Anna Katharine Green.