How to Say "Royalty" in Latin

domus rēgia

For royalty in the sense of the king and his family, Latin says domus rēgia, "the royal house".

domus rēgia refers to the whole royal family. rēgēs, "kings", can stand for royal persons in general.

Meaning: monarch and their families treated as a group (noun)

Which one should you use?

rēgnum means "a kingdom" or "royal power", not the royal persons.

DOH-moos RAY-gee-ah

Latin rēx belongs to an old family of words for "king", with relatives such as Sanskrit राजन् (rājan) and Gaulish -rīx, as in the name Vercingetorix.

"At puer Ascanius, cui cognomen Iulo / additur (Ilus erat, dum res stetit Ilia regno), / triginta magnos volvendis mensibus orbes / imperio explebit, regnumque ab sede Lavini / transferet, et Longam multa vi muniet Albam".
Then, too, the boy Ascanius, named of late / Iulus (Ilus was he in the day / when firm by royalty stood Ilium's state) / shall rule till thirty years complete the destined date. / He from Lavinium shall remove his seat, / and gird Long Alba for defence.
Tatoeba #6488353 by carlosalberto, translation #6785807 by carlosalberto
Tōta domus rēgia aderat.
All the royalty were present.
Domus rēgia in urbe habitat.
The royal family lives in the city.

Sources

⭐Share⭐ to appreciate human effort 🙏