Ropo chétach cétblíadnach...
Ropo chétach cétblíadnach, cech cét diib ar úair.
(may I be * hundredfold * hundred years * each * hundred * of them * by * time)
May I live for a hundred times a hundred years, each hundred of them in turn!
This supplication comes from a longer "ortha" (poem or incantation) for long life which begins "Ad·muiniur secht n-ingena trethan" ("I invoke the seven daughters of the sea"). Kuno Meyer edited and translated it in "Miscellanea Hibernica" and attributed it to Fer fio macc Fabri. P. L. Henry edited and translated it again much later in "Dánta Ban".
For another selection from this "ortha" , see "Trí bás úaim rohuccaiter" in this collection.