Indeed. It's a very clunky word, not least because it's unclear which syllable to stress.

I've variously heard people say both i-dem-PO-tent and i-DEM-po-tent. (In the latter, the "o" in "po" gets reduced to a schwa.)

When I don't want to sound snooty, I say rerunnable.

Fixed point is another way to get at it, although it requires your listener to know what that is.

The term is very well-established in mathematics (for e.g. matrices and transformations) that is the precisely correct term for this, and it is already widely used in CS. Inventing a new word would not be helpful in the long run.

What do you mean by 'nicer' word? I really honestly don't get it.

I mean if it were some consumer property, like say the size of a hard drive or such, then yeah makes some sense, for a term used in strictly in technical circles to describe a precise technical property, I don't understand what 'nicer' means.