Thaipusam or Thaipoosam is a Tamil Hindu festival celebrated on the first full moon day of the Tamil month of Thai coinciding with Pusam star. The festival is celebrated to commemorate the victory of Hindu god Murugan over the demon Surapadman. During the battle, Murugan is believed to have wielded a vel, a divine spear granted by his mother, Parvati.

The Tamil calendar is a sidereal solar calendar used by the Tamil people of the Indian subcontinent. It is also used in Puducherry, and by the Tamil population in Sri Lanka, Malaysia, Singapore, and Mauritius.