unfruitful

Instead of doing this and having fellowship with the unfruitful works of darkness, they must rather reprove them.

And they are unfruitful because, whilst they last, they yield no real satisfaction.

In those days, almost fifty years ago, and in a small pioneer town, the fields open to women were few and unfruitful.

It is difficult to say that this proposition is false, but it certainly appears to be unfruitful.