I don't really care too much about the
semantics involved. So if somebody else means something different by the term "bridge", hopefully they will explain their thinking so we can have a meaningful conversation. It really doesn't matter if I normally use the term differently in my lineage.
So to continue with the "bridge" example, we just use the term to describe when our arm(s) touch our opponent's arm(s) creating contact. The bridge may be open or closed. Since the general idea is to hit the other guy, being able to cross the bridge is obviously important. Having them cross it and hit us is important to avoid.
Anyway that's about it. Pretty basic and definitely not worth arguing about. If others have a different, deeper meaning, that's great. We are here to share, right?