I mostly agree with this, but I believe the pleural for dragons should be 'na dragu(fada)in'carinasanfey said:ARRRRGH stupid no fadas.
Do(fada)chas na dragu(fada)n
(Dóchas na dragúin)
Dragún is a fairly modern Irish word, I believe, derived from the English. You'll find older words that are more authentic but they are less specific to what we thing of as dragons, more 'monster serpents' eg. ollphéist