Corollary

A corollary is like a fact that comes from another fact.

Let's say you know that if you mix blue and yellow paint, you get green paint. A corollary of that fact is that if you mix yellow and blue paint, you also get green paint.

So a corollary is like a little rule that comes from a bigger rule. Just like you can get to different places from the same starting point by taking different paths, you can learn different little rules from the same big rule by thinking about it in different ways.