Trayodashi Vrata is those observed on the thirteenth day during the waxing phase of moon or Shukla Paksha in a Hindu lunar month. The most popular Trayodashi Vrat is the Ananga Trayodashi Vrat. Other vrats include the Kamatroyodashi in Chaitra month. The upvaas and fasting on the 13th day is usually dedicated to Lord Shiva.
Those observing fast on the thirteenth day during the Shukla Paksha in Magh month (January – February) worship Shiva and offer Til and sun-dried rice. Those observing fast on the day take honey.
The fast on thirteenth day in Poush month is dedicated to Yogeshwara. Kakola is worshipped in the Phalugna month and Shiva in Chaitra month. Those observing fast in on Trayodashi in Vaishaka month take only Jati fruits and worship Maharupa.
In Jaishta month, Pradumnya is worshipped and in Ashada, Shiva as the husband of Uma is worshipped. In Shravan Mahina Trayodashi, trident bearing Shulapani is worshipped and in Bhadra month the Sadyojata manifestation of Shiva is worshipped.
In Karthika month on Trayodashi tithi, Vishweshwara is worshipped. Shambhu is worshipped in Margashirsh month.
Usually during Trayodashi Vrat, a different manifestation of Lord is worshipped.
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