SlimJim at the Domain for Truth gives a great definition of a contradiction. He then goes on to show how to argue against the supposed contradictions in his post which you can read here. But for our purposes, I wanted to share his definition of a contradiction for my definitions page.
When dealing with skeptics’ claim of Bible contradictions it seems one can never be reminded enough of what exactly is a contradiction. A contradiction occurs when two or more claims conflict with one another so that they cannot simultaneously be true in the same sense and at the same time. To put it another way, a Bible contradiction exists when there are claims within the Bible that are mutually exclusive in the same sense and at the same time.