In the practice of the court of appeals, it means that the court of appeals has concluded that the lower court decision is correct and will stand as rendered by the lower court.
To assert (as a judgment or decree) as valid or confirmed.
To testify or declare by affirmation as distinguished from swearing an oath.
To uphold a judgment or decree of a lower court.
The Free (Legal) Dictionary
To ratify, establish, or reassert. To make a solemn and formal declaration, as a substitute for an oath, that the statements contained in an Affidavit are true or that a witness will tell the truth. In the practice of appellate courts, to declare a judgment, decree, or order valid and to concur in its correctness so that it must stand as rendered in the lower court. As a matter of Pleading, to allege or aver a matter of fact.
A judgment, decree, or order that is not affirmed is either remanded (sent back to the lower court with instructions to correct the irregularities noted in the appellate opinion) or reversed (changed by the appellate court so that the decision of the lower court is overturned).