The lunar calendar adds one extra month every third year. This extra month is known by various names: Adhik Maas, Mal Maas, Purushottam Maas and Malimmacha. This is the thirteenth month of the lunar calendar.
It is a fact that the solar year is made up of 365 days and about 06 minutes and the lunar year is made up of 354 days. Thus both the solar and the lunar years have gaps of 11 days, 1 hour, 31 minutes and 12 seconds. As this gap increases each year, it approximates in three years to one month.
Regarding Adhik Maas Hemadri says that Adhik Maaas Vrat is capable of washing away all the sins of people (who observe the Vrat). During this month fasting are undertaken and garments etc. are distributed to charities. A beautiful story relates to how, in ancient times, through the observance of Adhik Maaas Vrat, king Nahush was released from all bondage and acquired the throne of Indra (the ruler of gods in heaven).
As mentioned before, Adhik Maas is also known as Purushottama Maas. According to the lunar year, there were only 12 months. Each of the twelve months was assigned to 12 gods. So that the lunar and the solar years do not get out of step with days and seasons, the far-sighted Rishi-Munis calculated and facilitated Adhik Maas (extra month) and shown its importance. But one problem still remained. Each of the 12 months was assigned to 12 different gods. But the 13th extra month was not assigned to any god. Adhik Maas felt sadness and approached Lord Vishnu and said that no god was assigned to him (Adhik Maas) and for that reason he was called Mal Maas or Malimmucha. Adhik Maas further spoke to Lord Vishnu: ‘I am filled with anxiety and I have therefore come to seek your refuge and help.’
Lord Vishnu took pity on him. The Lord (Vishnu) agreed and assigned Adhik Maas to Himself and gave the name Purushottama Maas to this month. Lord Vishnu also said that acquisition of merits during other months through good deeds, japa, austerities etc can be acquired by japa, austerities etc. carried out within this one month. Since then it is known as the Purushottama Maas and acquired greater significance than the other months.
Some Hindu communities look upon this month as inauspicious time to perform wedding ceremonies and this confuses the young Hindu people in the community.
Why is the month which has the name of Lord Vishnu himself to be considered inauspicious to perform wedding ceremonies?
Well the answer is it is not inauspicious and you can have wedding ceremonies in Adhik Maas is also known as Purushottama Maas.