Antonyms for Concentrated (opposite meaning)
WordNet sense 1 ((of light) transmitted from a broad light source or reflected):
diffuse, soft, diffuse
WordNet sense 2 (not saturated; capable of dissolving more of a substance at a given temperature):
unsaturated
WordNet sense 3 (spread out or scattered about or divided up):
distributed
From the ODE community, based on WordNet
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