Reveled word of God, I think we can both agree on that. However I think you misunderstand what the Catechism is saying: reveled truth was always , except for the ten commandments, written by the hand of man and was usually originated in oral fashion:God speaking to man or God speaking through man. Some of this was written, some passed on as sacred Tradition. What was written is Scripture, but unlike the Koran, Christian Scripture is supported by the witness of the Church founded by Christ and shepherded by His apostles who passed on His teachings to their disciples. It is this witness with in the Church that gives us the confidence to know the Scriptures to be true. As St Augustine stated in his letter to Mani:
If you should find someone who does not yet believe in the gospel what would you [Mani] answer him when he says, “I do not believe”? Indeed, I would not believe the gospel myself if the authority of the Catholic Church did not move me to do so.
The Church cant "trump" Scripture nor can Sacred Tradition since they all derive form the same source.
As an example could you show the "revealed word of God" which led to the dogma of the Bodily Assumption of Mary? (Scriptural reference would be nice.) :)