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 is a compound name. Its parts are heri + vǫr — each an attested element with a recorded meaning of its own.
Hervor does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
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In Pythagorean numerology the letters of Hervor reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.