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 reduces to nine — the number of invincible protection.