Celestina is the Spanish and Italian form of Celestine — from the Latin caelestis (heavenly). A modern revival in the vintage-Iberian aesthetic. Saint Celestina is venerated in Italian tradition (a feminization of Pope Celestine V).
Celestina 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 Celestina reduce to 7, The Seeker. This is a traditional interpretive system, not a factual claim about the name.