A vice is a habit which is regarded as a weakness in someone's character, but not usually as a serious fault.
例句
His only vice is to get drunk on champagne after concluding a successful piece of business...他唯一的缺點就是在成功做成一筆生意后會大喝香檳而醉。Intellectual pretension was never one of his vices.他從來不附庸風雅。
N-UNCOUNT
（尤指與色情業、賣淫行為相關的）犯罪活動,惡行
Vice refers to criminal activities, especially those connected with pornography or prostitution.
例句
He said those responsible for offences connected with vice, gaming and drugs should be deported on conviction.他說，那些被指控與賣淫、賭博和吸毒有關的人一旦罪名成立就應該被驅逐出境。...allegations of how she worked in a 'seedy vice den'.對她在“骯臟淫窩”里如何工作的說法
N-COUNT
老虎鉗;臺鉗
A vice is a tool with a pair of parts that hold an object tightly while you do work on it.