> Paul Pritchard writes:
>
> >John Conway's helpful answer runs slightly astray at one point:
> >
> > "although the Greek prefixes tend to alter as they form compounds
> > (so for instance "penta" becomes "pente" in "penteconta" = 50),
> > this is less natural in English."
> >
> >This is the wrong way round: five is pente, fifty is penteconta
I'm sorry that that clause was rather brief; I didn't intend to say
(and didn't in fact say) that "five" in Greek was "penta".
About "octo/octa" the situation is less clear, because it seems that
for many words both forms have been used, both in Greek and English.
Despite what Paul says below, I believe this is true of "octagon/octogon",
and am fairly sure that in the 19th century, "octohedron" was more common
than "octahedron".
> >The Greeks will have had 'oktagon', so he who coined 'octagon' for English
> >knew what he was doing. What needs explaining is why we have 'octopus', not
> >'octapus' . (The answer is that both 'oktapous' and 'oktopous' are found
> >in reputable Greek writers, so even a pedant will probably admit that one
> >is entitled to draw on either form.)
This is really the point I wanted to make - because there hasn't been
an agreed standardization, we are to some extent free to choose our own.
> Conway's system is good, IMHO, and easily memorizable - where I disagree
> is the case of 100: he prefers the type hecto (or something like that).
In fact I now prefer "hecta" (which I fear you'll like even less!),
so as to uniformize the "-a" ending.
> I think that it would be: hecatonta-; again for uniforming reasons:
> triaconta-
> tetraconta-
> ....
> enneaconta-
> hecatonta- (or at least: hecaton-)
I don't at all mind "hecatontagon", but think that the fact that
"hecto/hecta" is a firmly established part of the international scientific
vocabulary will make "hectagon" more likely to be understood. Perhaps we
can agree that "hecatontagon" is its complete and formal name, of which
"hectagon" is a slangy abbreviation?
John Conway