Bodhi Day is a Buddhist holiday that commemorates the day that the Buddha achieved enlightenment, translated as bodhi in Sanskrit or Pali. Bodhi Day is celebrated on the eighth day of the 12th lunar month. In 2014, Bodhi day is observed on Monday, Dec. 8.

The Buddha was born as Siddhartha Gautama into a noble, privileged household. When he was close to 30 years old, he abandoned his material lifestyle and retreated to the forest seeking answers to the problem of suffering, specifically old age, sickness and death. According to tradition, he initially sought bodhi (enlightenment) through meditation, self-mortification and practicing other austerities.

After several years of intense practice, he realized that bodhi was to be found through meditation, but through a Middle Way, away from the extremes of self-mortification and self-indulgence. The story goes that he meditated in Bodh Gaya, a town in northeastern India, under a peepal tree (a species of Banyan fig), now famously known as the Bodhi tree, and resolved to continue meditating until he achieved bodhi (enlightenment).

It is believed that after 49 days of continuous meditation, during which he confronted Mara, the lord of desire, and his army of demons, Gautama achieved bodhi (enlightenment) at the age of 35. Since then he was known as the Buddha ('enlightened one').

Buddhists around the world consider Bodh Gaya, India to be the most sacred of holy places as the birth place of their tradition. Bodhi Day is celebrated in many mainstream Mahayana traditions including Zen and in Pureland Buddhist schools in China, Japan and Korea.