coarse, rough, rugged
粗 centers on a lack of refinement or smoothness: something coarse, rough, or rugged in texture or quality.
粗 combines 米 (rice) with 且, which likely contributes the sound and suggests something rough or unrefined, as in coarse rice.
Rice 米 that is not yet polished is rough and coarse. The right side 且 looks like a pile of uneven grains, reinforcing the idea of roughness.
For ソ, imagine coarse rice being sorted: the first sound of 'sort' cues ソ, and the rice is rough and unrefined.
coarse; rough
crude; rough; plain; humble; shabby; poor-quality; low-quality
coarse; crude; inferior
poor; lame; ill-prepared
mostly; almost; nearly; for the most part
rough (behaviour, temperament, etc.); wild; rude; violent
ore
carelessness; careless mistake; blunder
coarse; rough; crude
small present; trifling gift
coarse; rough; bulky
rustic; rude; vulgar; rough
osteoporosis
crude construction; crude manufacture
large-size refuse (e.g. furniture, electrical goods); oversized garbage; bulky rubbish
rough; crude; unrefined
simple diet; plain food; simple food; frugal meal
outline; summary; argument
coarse salt; unrefined salt
granulated sugar; brown sugar