Synonyms and related words :
angular, bony, flat, flat-chested, fleshless, gangling, gangly, gaunt, gawky, lank, lanky, lean, lean-fleshed, lean-looking, meager, scraggy, scrawny, skeletal, skinny, spare, spidery, spindling, spindly, thin-bellied, thin-fleshed, twiggy, undersized, underweight