Chaitra is a month

Month

A month is a unit of time, used with calendars, which was first used and invented in Mesopotamia, as a natural period related to the motion of the Moon; month and Moon are cognates. The traditional concept arose with the cycle of moon phases; such months are synodic months and last approximately...

 of the Hindu calendar

Hindu calendar

The hindu calendar used in ancient times has undergone many changes in the process of regionalization, and today there are several regional Indian calendars, as well as an Indian national calendar. Nepali calendar, Bengali calendar, Malayalam calendar, Tamil calendar, Telugu calendar, Kannada...

.

In India's national civil calendar

Indian national calendar

The Indian national calendar is the official civil calendar in use in India. It is used, alongside the Gregorian calendar, by The Gazette of India, news broadcasts by All India Radio, and calendars and communications issued by the Government of India.The term may also ambiguously refer to the...

 Chaitra is the first month of the year

Year

A year is the orbital period of the Earth moving around the Sun. For an observer on Earth, this corresponds to the period it takes the Sun to complete one course throughout the zodiac along the ecliptic....

 while it is the last month of the year in Nepali calendar

Nepali calendar

The Nepali Calendar is a traditional solar calendar used in Nepal for both civil and religious purposes. The year begins in the month Baishakh; usually around 14 April....

 where Baisakh

Vaisakha

Vaishakha or Baisakha is a month of the Hindu calendar. It is the first month of the Nepalese calendar and the Bengali calendar . In the Indian national calendar Vaisakha is the second month of the year, beginning on April 21 and ending on May 20.In the Hindu solar calendar, Vaisakha begins in...

 is the first month. With the calendar

Calendar

A calendar is a system of organizing days for social, religious, commercial, or administrative purposes. This is done by giving names to periods of time, typically days, weeks, months, and years. The name given to each day is known as a date. Periods in a calendar are usually, though not...

 reforms, it coincides with the northern spring equinox on March

March

March is in present time held to be the third month of the year in both the Julian and Gregorian calendars. It is one of the seven months which are 31 days long....

 20.

In the more traditional reckoning, the first month commences in March or April

April

April is the fourth month of the year in the Julian and Gregorian calendars, and one of four months with a length of 30 days. April was originally the second month of the Roman calendar, before January and February were added by King Numa Pompilius about 700 BC...

 of the Gregorian Calendar

Gregorian calendar

The Gregorian calendar, also known as the Western calendar, or Christian calendar, is the internationally accepted civil calendar. It was introduced by Pope Gregory XIII, after whom the calendar was named, by a decree signed on 24 February 1582, a papal bull known by its opening words Inter...

, depending upon whether the lunar or solar system is used.