The Trojan Reach, p18

When the Aslan destroyed Drinax and the survivors crowded into the Floating Palace, the divide between noble and commoner vanished overnight.
Back then, there were some twenty thousand survivors, split evenly between the titled aristocracy, courtiers and other nobility, and the servants and lower classes. Two hundred years of interbreeding grew the population to some forty thousand, and every single one of them has inherited at least one title. These titles are not used from day to day, but Drinax clings tightly to formality and ritual, so every plumber and hydroponic farmer in the Floating Palace can list their lineage and titles.

‣ has great info about noble titles, though not specific to the Kingdom of Drinax.
See also https://www.reddit.com/r/traveller/comments/1dj2v5g/drinaxi_nobility_titles/ and https://en.wikipedia.org/wiki/Imperial,_royal_and_noble_ranks

<aside> 💡 I like the idea that there would be a great many titles inherited that mean nothing now, such as Lord Duke of Alchinar, which was a city on Drinax that was destroyed - yet his great grandson still holds the title. (Many surely believe the titles will be meaningful again one day, when the Kingdom of Drinax is restored.)
And I think of the Logan’s Run episode where all the Sanctuary Project people had ancient titles they no longer understand and in no way reflect their role in the community.

(cf. Lwaxana Troi, daughter of the Fifth House, holder of the Sacred Chalice of Rixx, heir to the Holy Rings of Betazed.)

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