Out of the ten poruthams prescribed by South Indian Astrological rules, it is called as "Rasiyathipaty Porutham".
Hindu Rashi/ Nakshatra Matching
In South India, Rasiyathipaty Matching (Porutham) of the bride and groom. It is mostly done when the marriages are arranged by the families of the boy and the girl.
What is the meaning of Rasiyathipaty porutham?
The Rasiyathipaty porutham defines the friendliness quotient of the two charts being compared for marriage. Every birth chart has a Lord and when the Lords of the other chart is friendly or neutral, then the charts are said to match.
The Rasi and the respective Lords are given in the chart below.
The Rasi athipathi chart
Rasi Athipathi Mesha, Vrichika Mars Vrishaba, Thula Venus Mithuna, Kanni Mercury Kataka Moon Simha Sun Dhanu, Meena Jupiter Makara, Kumbha Saturn
Each house in the RASI chart is ruled by one of the Navagrahas (Planet).. Some planets have two places. The planet ruling the house of the Birth Star is 'RASI ADHIPATHI'. For example say a girl's Birth Star is ASWINI. Her Rasi is Mesham. Mesha Rasi Adhipathi is Chevvai. Now Boy's Star is SWATHI, his Rasi is Thulam. Thula Rasi Adhipathi is Sukran. The relationship between Chevvai and Sukran is Equal Status. This is Madhyamam - neither Very Good nor Bad. Acceptable. Rasi Adhipathi Porutham depends on the Relationship of the two planets ruling the house where Chandran is found in Rasi Chart.
If rasi lords of both boy and girl are mutual friends the result is uthamam.
If lords are equal the match is mathimam.
If they are enemy the match is athamam.