Also, i would call the home/home in the later stages a series, and as such playoffs, but on that point, it is just semantics.
A round-robin tournament (or all-play-all tournament) is a competition "in which each contestant meets all other contestants in turn" - Webster's Third New International Dictionary of the English Language, Unabridged (1971, G. & C. Merriam Co), p.1980
I was referring to what they did starting with the round of 16.
That's what I was referencing.
In which case, either/and: A: im confused by what you are saying B: we are arguing about semantics
from the UEFA site "Knockout phase
From the last 16 until the semi-finals, clubs play two matches against each other on a home-and-away basis with the same rules as the qualifying and play-off rounds applied. In the last 16, group winners play runners-up other than teams from their own pool or nation, while from the quarter-finals on the draw is free."http://www.uefa.com/uefachampionsleague/season=2013/matches/round=2000348/index.html
that is exactly what i would call playoffs/postseason(because, to me, they are the same words, po/ps)
there is a ladder involved, and the winner of the home and home series moves on to face the winner of another home and home, and so forth, until the final, which is a single game. this ladder structure is what playoffs are all to me, and not a round robin.
a round robin to me would be
A, B,C, D are in the championships
AvB, AvC, AvD
BvA, Bvc, BvD
CvA, CvB, CvD
DvA, DvB, DvC
and the winner would be declared the person with the most points, like in the french league for soccer.
playoffs(im rambling a bit, just to make sure I'm kinda going clear)
A,B, C, D again
and then, winner of AD v winner of BC, and the winner of that is the championship, and that is what i call playoffs.