"Il cuoio dell'uomo"
Is the translation still saying "dell'"? In Italian, they combine common prepositions with the definite article. "dell'" is used before singular nouns both masculine and feminine. It is a contraction of "di il" or "di la" and means "of the". For masculine nouns that don't start with a vowel or "s" and a second consonant or a "z", you would use "del". For masculine nouns that start with "s" plus a second consonant or start with a "z", you would use "dello". And for feminine nouns that start with a consonant, you would use "della".
dell'uomo - of the man
dell'arancia- of the orange - il succo dell'arancia - the juice of the orange or orange juice
del ragazzo - of the boy
dello zoo - of the zoo
dello sport - of the sport or of sport. See Gazzetta dello Sport - the Newspaper of Sport
della donna - of the woman.