Hervör (Hervǫr) comes from the Old Norse her (army, host) and vǫr (cautious, watchful) — meaning "warrior of the host" or "vigilant guardian." In the Saga of Hervör (13th century), Hervör is a shieldmaiden who takes up her dead father's sword Tyrfingr.
Hervör is rare even in modern Scandinavia.
Hervor reduces to three — the number of saga warrior.