A more thorough explanation:

Definition: A case that a court may for good reason accelerate and try ahead of other cases.

Example: A case involving a terminally ill patient who needs urgent medical treatment may be considered a preferred cause and given priority over other cases.

This means that the court will hear and decide on the preferred cause before other cases that are waiting to be heard. The reason for this is that the preferred cause is considered more urgent or important than other cases. For example, in the given example, the patient's life may be at risk if the case is not heard and decided quickly.