Meerabai is from the Sanskrit mīrā (मीरा — ocean) + bāī (बाई — Marwari feminine honorific). Mirabai (c. 1498-1547) was a Hindu mystic, Krishna devotee, Bhakti saint-poet, and princess of Mewar.
Meerabai 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 Meerabai reduce to 9, The Giver. This is a traditional interpretive system, not a factual claim about the name.