Opposite words for concentrated:
watery, shared, encyclical, scattered, dealt out, diffuse, light, watered-down, dispersed, unfocused, uncondensed, spread-out, mild, separated, deficient, fanned, weakened, parceled out, thinned, unfocussed, diffused, shared out, straggly, meted out, widespread, fragmentary, dilute, halfway, far-flung, doled out, fragmental, unconcentrated, apportioned, spread, broken, spaced, incomplete, splashed, divided, thin, partial, dispensed, low-density, diluted, rationed, distributed, delicate, sparse, divided up, weak, unsaturated.
Usage samples:
  1. His attention would be concentrated on what they were doing.
    "The Grell Mystery", Frank Froest.
  2. Lucien's mother and sister had concentrated all their tenderness on him, David was his devoted friend; he was accustomed to see the three making every effort for him in secret, and consequently he had all the faults of a spoiled eldest son.
    "Two Poets Lost Illusions Part I", Honore de Balzac.
  3. Returning to the other room, he proceeded to load up a saddle- bag with a supply of the most concentrated and therefore portable provisions, sufficient to last him several days; but, to all appearances, hardly enough to last him for one.
    "Harley Greenoak's Charge", Bertram Mitford.
  4. At Emden, with its direct cable to the theatre of war in England, was concentrated the brain of the whole movement.
    "The Invasion", William Le Queux.