alt Hacker News> if everyone understands ... then what's the problem
"E-paper" means very little. It may mean "static" (and yet not necessarily "bistable", not even necessarily "efficient"), it may mean "reflective"... It is a marketing term.
So no, there is no real "agreed understanding" in it.
It's not just a marketing term. Everyone agrees that it means reflective screen, with reflectivity somewhat approaching real paper.