Durga (दुर्गा) means "the invincible" or "the impassable" in Sanskrit. She is the Hindu warrior goddess — the fierce protective form of Parvati, slayer of the buffalo demon Mahishasura.
Durga is celebrated during Navratri and Durga Puja — the most important Hindu festivals in Bengal.
Durga 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 Durga reduce to 6, The Nurturer. This is a traditional interpretive system, not a factual claim about the name.