Rosemary comes from the Latin ros marinus — meaning "dew of the sea" — referring to the Mediterranean herb that grows wild along sea cliffs.
Rosemary was popular in the mid-20th century, peaking at #54 in 1944 — Rosemary Clooney was a major star. After decades of decline, the name is returning. Today it sits in the U.S. top 500 and is climbing.
Rosemary 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.
In Pythagorean numerology the letters of Rosemary reduce to 6, The Nurturer. This is a traditional interpretive system, not a factual claim about the name.