In olden days lower CAST people were severely criticized...
Castigated sounds similar to castrated, which would be a harsh punishment for any guy.
If you have to throw a criminal out of the GATES of society, CAST him out the GATE - CASTiGATion...
u criticize severely and punish those who ask ur CASTE at the GATE
one who follws CASTEism is thrown out of the GATE
castigation sounds like rustication.
In Iran, if you break your chastity you will suffer chastisement. In USA, if you do caste discrimination, you will suffer castigation.
Inter caste Marriage will result in punishment; severe criticism or disapproval. (castigation -> gate for love using caste)
castigation -> gate for love using caste, if broken punishment & disapproval
CASTIGATION we cast gold to get its finest level same way we SCOLD or PUNISH to make them proper.
"Castigation" sounds like "caste at every gate of the nation" which acts as a punishment and severe disapproval due to the use of caste quota..