The Collaborative International Dictionary of English v.0.48:
graininess \graininess\ n. the quality of being composed of relatively large particles. Syn: coarseness, granularity. [WordNet 1.5]WordNet (r) 3.0 (2006):
graininess n 1: the quality of being composed of relatively large particles [syn: coarseness, graininess, granularity]