Vashti comes from the Old Persian vahišta, meaning "beautiful" or "the best." In the Book of Esther, Vashti is the Persian queen who refuses King Ahasuerus's order to display her beauty to his banquet guests — and is deposed, making way for Esther.
Vashti has been embraced by Jewish feminist tradition as a figure of dignity and refusal. The singer Vashti Bunyan is a contemporary bearer.
Vashti 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 Vashti reduce to 7, The Seeker. This is a traditional interpretive system, not a factual claim about the name.