Final answer:
The correct term when an appellate court leaves a lower court's verdict unchanged is to 'uphold' the decision.
Step-by-step explanation:
The term that refers to an appellate court's action of leaving the verdict of a lower court unchanged is uphold. When a higher court, such as an appellate court or the Supreme Court, decides to uphold a decision, they agree with the ruling of the lower court and determine that no change is necessary. In contrast, to remand means to send the case back to the lower court for further action, to reverse means to overturn the lower court's decision, and an appeal refers to the act of formally requesting a higher court to reevaluate the lower court's decision.