Does anyone have a way of defining when a word is officially accepted into a language? For example, from the wikipedia list, I only identify mammoth, bridge, steppe, pogrom, vodka, pavlova and maybe shashlik as being English words. The others are merely Russian words which English speakers use when appropriate.

Similarly, I would consider chauffeur to be an English word from French, joie de vivre to still be french and jus to be somewhere in the middle (it has caused no end of Scrabble arguments).