In this forum one comes across the term "shuddh Hindi" now and again while on other occasions the expression "pure Hindi" is mentioned. A few quotes are given below, just to illustrate the point. "Um, Standard Hindi sounds nice, but I am not a huge huge fan of it. Although, Shudhh (pure) Hindi has a nice sound to it". (panjabigator: 29/06/2006) "Right... Many people use "jimmedaari" for "daayitva", though I know people who are good at Hindi, and they use Dayitva. It is charming to listen to pure Hindi words in conversations in Hindi". (rahulbemba: 31/08/2011) "I have Hindi as mother tongue and I know the examples are too many... Many of my friends who speak pure Hindi (with fewer insertions of English and foreign words which are so common now in cities), they use व/ "va". Even I use it when I write in Hindi, but almost none in spoken Hindi, personally". (RB 20/09/2011) The obvious meanings that one can take from "shuddh" and "pure" are "unadulterated", "uncontaminated", "unpolluted", "clean", "untainted" and so on. My enquiry concerns this concept of purity in connection with Hindi in particular and other languages in general. What is it that constitutes "shuddhataa" if this notion is at all possible and if "English and foreign words" as mentioned in the above quotation do intrude into a language, what quantifiable level would this unwelcome presence need to reach when the said language is no longer "shuddh"?