The term Regalian was used in the 24th century to denote various items and ideas.

The Gatherers were in possession of Regalian phaser rifles. (TNG: "The Vengeance Factor")

Captain Jean-Luc Picard needed to study up on Regalian law before conducting a mediation the miners on Pentarus V in 2367. (TNG: "Final Mission")

Quark imported some Regalian fleaspiders and Regalian liquid crystals together. (DS9: "The Ship")