merchant [merchants](person who traffics in commodities) noun [UK: ˈmɜː.tʃənt] [US: ˈmɝː.tʃənt]Mr Brown is a wool merchant. = Il signor Brown è un commerciante di lana.
trader [traders](one who earns a living by trading) noun [UK: ˈtreɪ.də(r)] [US: ˈtreɪ.dər]I'm a trader. = Sono un commerciante.
commerciante d'arte noun
art dealer(someone who buys and sells works of art) noun [UK: ɑːt ˈdiː.lə(r)] [US: ˈɑːrt ˈdiː.lər]