Thin indica una extensión relativamente pequeña entre dos superficies, o en diámetro <thin wire>, o puede bien connotar falta de sustancia, riqueza o abundancia <soup that was thin and tasteless>. antonyms: thick, fat, wide
Slender indica delgadez o magrez, a menudo acompañadas de gracia y proporción <the chair's slender legs>. antonyms: broad
Slim se aplica a una esbeltez que connota fragilidad o escasez <the plan had only a slim chance of success>.
Slight indica pequeñez al igual que delgadez <though he was as slight as a boy, he was wiry and strong>. antonyms: stout
Tenuous indica una extrema delgadez, delicadeza o falta de sustancia y de firmeza <had tenuous family connections with the president>.