Falak is from the Arabic فلك (Falak — celestial sphere, sky, orbit). Falak is one of the Arabic feminine names — central to traditional Muslim heritage. Arabic feminine name reflecting Islamic cosmological heritage.
Falak 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 Falak reduce to 4, The Builder. This is a traditional interpretive system, not a factual claim about the name.