What is the best way to translate the western concept of an open marriage? I was thinking "Pluramemo", however some people call themselves by that title but just mean that they are a loving, caring person who likes to have friends, so the term has been watered down.
The Esperanto Wikipedia article on polyamory uses the literal translation malfermita geedzeco (accordingly partnereco etc.), which I have seen in other places, too. Another, less metaphorical expression I myself prefer, however, is neekskluziva geedzeco "non-exclusive marriage" (also this adjective can be found the article).
I haven’t heard of the meaning of pluramemo being diluted and as far as I’m aware most people would assume it has the same meaning as polyamoury, ie, the practice of having more than one intimate relationship at a time.
However, that doesn’t say anything about whether the people are married or not so I don’t think it would be a good translation of open marriage. I would opt for the same suggestion as Cyril Brosch malfermita geedzeco. This however opens up the debate about the annoying problems with the edz- root and whether geedzeco excludes gay marriage.