Hmm. Well, neither of you quite answered my question. What I was asking, simply, was: do you believe that anyone senior to you is "sempai" and anyone junior to you is "kohai"?
Please verbally smite me if I'm wrong on this, but through my readings I have come to believe that the English definitions are as follows:
-Sempai is someone who was training at the dojo prior to your own joining.
-Dohai is someone who started on the same day.
-Kohai is someone who started after you.
On the other hand, like most things Japanese-turned-English, It implies more in its native land. It is considered a permanent title once given, no? If Joe is my Sempai and he leaves the dojo, and I continue to train, if he returns a dozen years later he is still my Sempai, despite my technical advancements.
This is, by my reckoning, the definition.