N-COUNT （金融机构中不具备相关知识或未经上级批准就进行交易的）流氓交易员 A rogue trader is an employee of a financial institution who carries out business without the knowledge or approval of his or her bosses. （金融机构中不具备相关知识或未经上级批准就进行交易的）流氓交易员 [business, disapproval]
...the unauthorised dealings by rogue trader Nick Leeson which brought down the bank.