well-defined

By contrast, exercising requires you to commit your willpower for only a short, well-defined period of time.

Pawson smiled faintly, then his eyebrows lost their identity in some well-defined wrinkles in his forehead.

As between ‘our’ activities as ‘we’ experience them, and those of our ideas, or of our brain-cells, the issue is well-defined.

They were soon in the woods and saw a well-defined path running to the eastward.