Thevar is a backward caste 

Dalits and Human Rights: Dalits: the broken future By Prem Kumar ShindeTake our survey New!   page 91

http://books.google.com/books?id=xFw6aBjJOKsC&pg;=PA91&dq;=thevar+backward+caste&hl;=en#v=onepage&q;=thevar%20backward%20caste&f;=false

Betrayal of Indian democracy By M. B. ChandeTake our survey New!   page 75

http://books.google.com/books?id=fEhXiAnWXA4C&pg;=PA75&dq;=thevar+backward+caste&hl;=en#v=onepage&q;=thevar%20backward%20caste&f;=false

Devar is being confused with thevar.