Mark J. Reed wrote:

> Several calendars, starting with the ancient Egyptian, are solar with a
> basic structure of 12 30-day months followed by 5 extra days called the
> "epagomenae" (or "epagomenal days" in the boring English version).  Later
> revisions introduced the concept of leap years, in which there was a 6th
> epagomenal day.  My question is simple: what's the singular form of
> "epagomenae"?   Is it "epgaomena"?  It looks Greek in origin rather than
> Latin (although the -ae makes me suspicious; maybe it's a Latinization of 
> a
> Greek borrowing), and my Greek knowledge is pretty much limited to the
> alphabet.

Quite a bit on Google (both the -ae and -al forms), but no etymology. Nor in 
the online AHD (shame shame!!). Shorter-OED gives _epagomenic_ (< Gk. 
epagomene: ['e:mera]) 'intercalary [day]'-- that's probably fem. sing. but 
am not sure....  It would seem to be related to _epact_, which has something 
to do with the same matter.
My Greek is non-existent, too; it appears to be an -omen(os/e:/on) 
participle, and I'd suspect it must mean something like "inserted" or maybe 
"left over", but I had no luck using the online dictionaries. We need Ray 
B.!!!

My guess too would be that -ae is a latinization, < "dies ...." (plural); 
the Lat. sing. would be epagomena, but in view of our doubts, maybe you 
should stick to "epagomenal day..." (I don't know how one Anglicizes a 
Gk. -men- participle, no ex. springs to mind-- well, there's phenomenon, but 
that's a neuter.)