Thiru

In Tamil, honorifics (Tamil: முறை, muṟai) governs daily speech and register of both written and spoken communication. Traditionally, Tamil has been classified into two registers viz செந்தமிழ் (Centamiḻ) meaning 'classical' or 'pure ' Tamil and கொடுந்தமிழ் (Koṭuntamiḻ) meaning 'corrupt' Tamil. A huge feature of this difference is honorifics. Tamil honorifics usually are suffixes, although prefixes are not uncommon.

Lexical choice plays a vital role in Tamil society as depending on the choice of words, the register may alter.

Not all words in Tamil necessarily have a different colloquial, low, standard and high equivalents.

Tamil nouns can end in ன் (n), ள் (ḷ) or ர் (r). ன் (n) and ள் (ḷ) are used to people of lesser social order to denote male and female respectively. ர் (r) is used as a form of respect to a person of higher social order.

Reflecting the importance of this ending, some Tamil castes have re-configured their caste names to end in /r/ rather than /n/, rendering them honorific. Such castes include the Pallar (formerly Pallan) and Paraiyar (formerly Paraiyan).

கார் (Kār) is a singular honorific suffix to refer to a single collective noun. காரர் (Kārar) is a higher form of கார் (Kār). For example, கடைக்கார் (kaṭaikār) means 'shop-keeper' while கடைக்காரர் (kaṭaikārar) can be translated as 'honourable shop-keeper'. It is used to show and maintain a respectful distance in a relationship, as such is used to refer to stranger(s).

மார் (Mār) is a plural honorific suffix used to refer to a collective noun. மாரர் (Mārar) is a higher form of மார் (Mār). For example, அக்காக்கள் (akkākkal) means 'elder sisters' and is a plural, அக்காமார் (Akkāmār) means 'those honourable elder sisters' and is a collective plural while அக்காமாரர் (Akkāmārar) can be translated as 'those venerable elder sisters' and is also a collective plural. It is used to show respectful closeness or appraisal in a relationship, as such is used to refer to familiar person(s).

னார் (Nār), ஞர் (ñar) and யார் (yār) is an honorific suffix affixed after a noun to highlight its influence or importance. Its use implies that the noun is a collective singular. The rules to conjugate them are as follows: if the noun ends with ன், its ending would be னார் (Nār); if a noun ends with ஞன் (ñan), its ending would be ஞர் (ñar); if a noun ends with ஐ (ai) or இ (i), its ending would be யார் (yār).

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Wikipedia