Iskra (Искра) is the Bulgarian and Slavic word for "spark." The word was famously used by Lenin as the name of his revolutionary newspaper in 1900-1903.
Iskra is widely used in Bulgaria and the broader Slavic world.
Iskra 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 Iskra reduce to 4, The Builder. This is a traditional interpretive system, not a factual claim about the name.