Originally posted by Bill Martino
Who can know for sure? In places where the literacy rate is very low it's quite easy for words to become corrupted.
Hate to interject-but this is my area of expertise, language-change:
(1) 'corruption' is loaded term used to 'code' one language as being better than another. Language changes, it's just what happens. Is Modern English corrupted from Old English? Is American English corrupt compared to British English? (OK-the latter one's a bad example

)
Of course, in a sense all non-Sanskrit languages are corrupt compared to Sanskrit, if one uses Sanskrit terminology

. Sanskrit means 'perfected'! As opposed to 'Prakrit' (a Sanskrit term for non-Sanskrit Indic languages, like Hindi, Gurkhali, Bengali, &c.), which means 'rough, raw, natural, unformed'.
(2) I don't think literacy rate has much to do with language change. Look at the vast number of English dialects. There's quite a bit of difference between a Cockney or Estruary-English speaker, an Australian speaker, a Texan speaker, a RP speaker, a General American speaker, a Philadelphia speaker, a Boston speaker, a South-African speaker, &c., even if we just consider the literate middle-class for instance. And a lot of these changes have happened in the hundred years--I don't think reading/writing ability has much to do with changing pronounciation and changes in syntax.
Sorry for the pseudo-'lecture'

--but, being my profession, I feel obliged to disillusion people from the viewpoint that language evolves/is corrupted. That doesn't mean I don't have views on what sorts of English are 'correct' (or that other people can't), but I realise that those views are subjective, social judgements-- not 'scientific' ones.
Though I think your point was probably that no 'records' have been kept so that one couldn't trace the origin of a Nepalese word. However, most languages don't have such records--one can most likely guesses at origins by comparing words in related languages and trying to pick out systematicity in types of change ('corruption').
cheers, B.