"Ellipses" is the plural of "ellipse", and also of "ellipsis". This is a pretty insignificant linguistic problem, but it's still a problem. We've got two words here which share an etymology, but they have diverged in meaning and usage. That would be fine - I think we're better off with two different words for a conic section and an omission. However, the fact that the words used to be used interchangably leaves them with the same plural form. This would be far more confusing and irritating if they were both common words, but it still occasionally bothers me when I'm referring to strings of three periods, and I look at what I just typed and wonder if someone will think I'm talking about ovals.
I don't have much to say here, but it was a nodeshell rescue that happened to coincide with something that always nags at the back of my mind.
Gritchka pointed out that the same problem exists with "bases" - it's the plural of both "base" and "basis". This looks especially awkward to me as the plural of "basis", but I can't think of a less unwieldy neologism that I'd replace it with.
All your bases...