month/māsa

मास/māsa

By Sanjay Prabhakaran

A month or the 12th part of the Hindu year.

There are 4 kinds of Measuring months , viz.

1. सौर/saura/saura ;the solar
2. सावन/sāvana/sAvana; the natural
3. नाक्षत्र/nākṣatra/nAkSatra; the stellar
4. चान्द्र/cāndra/cAndra; the lunar;

सौर/saura/saura ;the solar

This consists consists of suns transit into every Zodiacal sign called Rashi of 30 degrees each. Each month is named after the Sign name eg dhanur maasa when sun is in Saggittarius.
Word meaning sura = surya, expanding gives "saura" = from Surya, Note the "au" to indicate derivation.

सावन/sāvana/sAvana; the natural

This consists of 30 Earth Days, i.e 30 Sunrise/Sunset counts as one month. Ahargana (aha= day gana = count) keeps tracks of total number of days. Refer any panchanga to get the ahargana count.
Word meaning : savana = 3 times a day oblation, saavana is the expanded form, meaning 'from savana'. (For counting the total number of oblations done).

नाक्षत्र/nākṣatra/nAkSatra; the stellar

This also called Sidereal month in english. The period of revolution of moon around the Zodiac is called one month in this notation, has mean value of 27.32166 days. This is used to adhaana chart (gestation chart) etc to count months in pregnency.
[Ref: In the 1850’s, a Dr. Naegele determined the average length of human gestation was 266 days from conception, or 280 days (40 weeks) from last menstrual period. He assumed that the average woman had cycles that lasted 28 days and that she ovulated on Day 14 of her cycle. He used his data to come up with a mathematical calculation for due dates]

Word meaning : nakshatra = lunar mansion, Naakshatra is derived form to indicate it's from be nakshatra. Note "aa" inbetween to show the derivation.

चान्द्र/cāndra/cAndra; the lunar;

Consists of 30 Tithis forming the Lunar Calendar,
This form of measuring a month in english is also called the Synodical Month is the interval of time between two identical phases and has a mean value of 29.53059 days. It consists of,

1. Krishna paksha (krishan=dark, paksha=side), Waning phase, Reducing Moon.
2. Shukla paksha (shukla = bright paksha=side), Waxing phase, Increasing Moon.

Each is divided in 15 Parts called tithiamsha. Each day is called a tithi. The approximate nakshatra in which full moon occurs is the name given to the Month, For example the Karthika maasa the approximate full moon occurs in Krittika nakshatra, Ashaada when full moon can happen in Purva-ashaad etc