I have always liked the terms early downwind and late downwind with everything in between simply being downwind (early downwind being up to the upwind threshold and late downwind being beyond the arrival threshold).
What do others think / do?
I took the radio exam not very long ago, and both the examiner and the (very nice) person who helped me prepare insisted that one call "downwind" when abeam the opposite threshold i.e. right after turning from crosswind leg into downwind leg. Further down it is called "middle of downwind" or "end of downwind" or "two-thirds downwind" or whatever.
Both persons also insisted there exists no such thing as "left-hand downwind" in ICAO phraseology - one is either on right-hand downwind or simply on downwind - which is left-hand by definition.