The phrase is: siardhóchas but I have also been told síordhóchais
Is one or both of these correct?
I suspect that the intent was to say one of these:
siardhúchas - "western homeland"
or
síordhúchas - "eternal homeland"
The second one works grammatically, but I'm not sure about the first one.
In either case, if they work, then with the ending changed to
-ais, the word goes into the genitive case (but needs an extra "
t" as well if the word "the" is added, as shown below:
[an] tsiardhúchais - "of [the] western homeland"
[an] tsíordhúchais - "of [the] eternal homeland"