Protector

From Memory Alpha, the free Star Trek reference.

Protector is a title used by several alien races.

Colyus (or at least the hologram based on him) was a Yaderan Protector. He became Protector in the early 2360s. (DS9: "Shadowplay")

Protector was a title given to leaders in Kelemane's species. (VOY: "Blink of an Eye")