Katyayani (कात्यायनी) is an aspect of Mahadevi and the slayer of the tyrannical demon Mahishasura. She is the sixth among the Navadurgas, the nine forms of Hindu goddess Durga who are worshipped during the festival of Navaratri. She is depicted with four, ten or eighteen hands. This is the second name given to the goddess Adi Parashakti in Amarakosha, the Sanskrit lexicon.

Navadurga, also spelled Navdurga and Navadurgas, are nine manifestations and forms of Durga in Hinduism, especially worshipped during Navaratri and Durga Puja. They are often considered collectively as a single deity, mainly among the followers of Shaktism and Shaivism sect of Hinduism.