I may have mentioned earlier that I – like Cyril, incidentally – make a point of reading several hours of Wikipedia daily. I recall first stumbling upon the word “necropolis” somewhere on Wiki when I was, I think, in the third grade; I remember wondering precisely what its plural is at the time. About three years later, when I’d learnt enough Greek and Latin to actually somewhat understand English, I attempted to independently derive a plural form, and arrived at the generally accepted “necropoleis”. Here’s how.
I began with the assumption that I’d like to preserve the “Greekness” of the term, and consequently decided that, whilst “necropoles” is viable (given that “necropolis” should be third declension in Latin), I’d like to go elsewhere.
In Greek, “necropolis” is irregular in that the nominative case follows a different root – πολις, specifically, as opposed to πολεος. In the spirit of irregular noun endings, we remove -ος from the genitive to claim the stem πολε-, add -ες for a rather lopsided πολεες, and contract εε into an epsilon-iota digraph (ει). Adding this modified ending to νεκρό-, we arrive at νεκρόπολεις, or “necropoleis”.
Of course, if one is going to go with English terms, then “necropolises” is more than acceptable, if slightly clunky.
Although none of this is particularly difficult to realize, “necropolis” and its plurals did float around my notebooks for a couple of years, so I reasoned that I should finally post this tidbit. The Greek- and Latin-related components of this post also prompt me to think of Greeklish, the CMD phenomenon that consists of the Latin alphabet’s being used in Greek online communication; I will try to discuss it at some point in the future.