WordNet sense 1 (a small worthless amount):

jack, shit, diddley, diddly, diddlyshit, diddly-shit, diddlysquat, diddly-squat, doodly-squat

WordNet sense 2 (short and thick; as e.g. having short legs and heavy musculature):

chunky, dumpy, stumpy, low-set, squatty

WordNet sense 3 (low in stature; not tall):

short

WordNet sense 4 (sit on one's heels):

crouch, hunker, scrunch, hunker down, scrunch up

WordNet sense 5 (having a low center of gravity; built low to the ground):

underslung

WordNet sense 6 (literal meanings; being at or having a relatively small elevation or upward extension):

low

WordNet sense 7 (exercising by repeatedly assuming a crouching position with the knees bent; strengthens the leg muscles):

squatting, knee bend