The name 'Enthiran' struck me as a very interesting example of a feature that Tamizh shares with Telugu, but does not share with Kannada (or any other language I know). The use of the male nominative case suffix '-an' is a brilliant way of making 'Enthiram' (machine) into 'machine-man'. In Telugu, I'd do it like 'Yantrudu' (with 'Yantramu' for the machine).
Two features are important:
1. The nominative case suffix should be quite distinct for the masculine gender compared to the neuter gender. The '-an' and '-am' difference in Tamizh, and the '-mu' and '-du' difference in Telugu are sufficient, but there's nothing comparable in Kannada. Hindi or English don't use case suffixes, so they are totally out.
Kannada is weird because it has a nominative case suffix that is used in formal writing that makes sense only when used in a sentence, and not independently. 'Ramanu' can never exist independently as a word (while 'Rama' can).
Sanskrit does make a clear enough distinction, with 'yantram' and 'yantraH', but:
2. The gender of words should be dependent purely on the gender of the object. Else, there's nothing to do!
I wish the movie was half as clever as the name, though :-)