featherlight, light, lightweight, underweight, weightless

bantam, diminutive, little, minute, puny, small, smallish, tiny, undersized(also undersize), weeflimsy, fragile, insubstantialpetite, slender, slight, slim, thin

heavy, hefty, leaden, overweight, ponderous, weighty

big, considerable, extensive, goodly, great, handsome, huge, hulking, jumbo, king-size(or king-sized), large, largish, massive, overscale(or overscaled), oversize(or oversized), sizable(or sizeable), substantial, super, voluminous, whackingbulky, cumbersome, unwieldy