Masik Shivratri is a monthly spiritual observance dedicated to Lord Shiva, falling on the fourteenth day (Chaturdashi) of the waning fortnight (Krishna Paksha) in every Hindu lunar month. It occurs during the darkest night preceding the new moon (Amavasya).
The observance is anchored to the Nishita Kaal, the sacred midnight window when Lord Shiva's transcendental linga form manifested for the preservation of creation. Devotees maintain a day-long fast, broken only the following morning, and perform night vigils (jagran) accompanied by chanting the Panchakshari mantra (Om Namah Shivaya).
Ritual worship involves performing abhisheka on the Shiva Lingam with milk, curd, honey, ghee, water, and unbroken rice grains, adorned with bilva (bael) leaves. While observed every month, the Masik Shivratri occurring in the month of Magha or Phalguna is celebrated nationally as Maha Shivratri.