arbitrageur
ar•bi•trageBrE /ˈɑːbɪtrɑːʒ/
BrE /ˈɑːbɪtrɪdʒ/NAmE /ˈɑːrbətrɑːʒ/
noun[uncountable] (business)the practice of buying sth (for example, shares or foreign money) in one place and selling it in another place where the price is higher 
word origin
ar•bi•tra•geur /BrE ˌɑːbɪtrɑːˈʒɜː(r); NAmE ˌɑːrbətrɑːˈʒɜːr/ (also ar•bi•trager /BrE ˈɑːbɪtrɪdʒə(r); NAmE ˈɑːrbətrɑːʒər/) noun
one of Wall Street's most famous arbitrageurs
