the situation in which something is helpful or useful in a particular situation, but sometimes not morally acceptable

As a matter of expedience, we will not be taking on any new staff this year. 迫不得已，我们公司今年将不招新员工。

I think this government operates on the basis of expediency, not of principle. 我认为这届政府做事毫无原则，只顾眼前之事。