-father's father. usage now is 'thatha'(father's mother) Not in use now except amongst Palghat Iyers (Mother's father) Used in this sense by Palghat Iyers only. Rest use for paternal grandpa also (mother's mother) used now for paternal grandmother also./ grandson/ grand daughter// - father///- mother-son-daughter- daughter in law-used for sister's daughter also./-son in law. former used for sister'a son also/- father's younger brother. Also husband of mother's younger sister/father's younger brother's wife; also mother's younger sister/-father's elder brother & mother's elder sister's husband/-father's elder brother's wife & mother's elder sister/- mother's brother (in some communities sister's husband)- mother's brother's wife- Father's sister (in some communities wife of mother's brother; mother in law)/- Father's sister's husband. The latter among Tamil brahmins denotes elder sister's husband)-Elder brother///- Elder brother's wife; second used by Iyengars, third by Iyers, and fourth colloquial usage-younger brother/- elder sister-younger sister/- wife's brother/- wife's sister//= wife's sister's husband. The last used by brahmins/- husband's brother's wife- relationship between two women marrying same person- relation between fathers of a couple; with addition of 'ammaaL' to this, relation between mothers of a couple will be denoted./- mother's brother's son- used rarely by brahmins - mother's brother's daughter- used rarely by brahmins- Father's sister's son. (nowadays used by some women while addressing husband)- father's sister's daughter- Rarely used by brahmins- a synonym of 'maithunan'. Also used colloquially while addressing brothers in law. In some communities used as a form of address of husband also. A popular word amongst teenager students and youngsters to address each other.- father in law-mother in law husband's younger brother (in some communities) husband's younger sister ( -do-)/- husband's sister- great grandfather ( rural usage) - great grand father -great grand mother -great great grand father - great great grand mother- husband's elder brother ( IN RARE USE NOW) - -do-'s wife -do- Also used to denote the first wife of a man - the second wife of a man- Colloquial usage that denotes sometimes mother and sometimes grandmother- - colloquial use to denote the woman of the house akin to lady.- A form of respectful address to elders, teachers and persons of higher status. In some villages used to denote father.No caste is majority.By population order (I added all subcastes into single caste),Naadar ~25%

Vanniars form ~13%

Kongu Vellalar Gounders form ~8%.

Thevars form ~7%.

Chettiar (excluding Kannada/Telugu origin), Muthaliars, Pillai (tot ~15%).

Scheduled Castes like Paraiyyar, Pallar, Sakkiliar, others together ~20%.

Tamil Brahmins ~3%

~7% is formed by other minor Tamil castes

~15% by non-Tamil origin people like Chettairs (Kannada/Telugu), Naidus/Reddies (Telugu), Nairs (Mallu), Kannadigas and North-Indians