a satoshi is the smallest monetary unit in the Bitcoin cryptocurrency, and is named after Satoshi Nakamoto, theprobably pseudonymousdeveloper(s) of Bitcoin.
I'm not sure if there would be any impact on bitcoin's popularity but it's good that the word has been acknowledged although I think it's a bit late.
Dictionaries are one of the most used things by people. The listing of "satoshi" word in Oxford English Dictionary will definitely help Bitcoin's popularity increase too I think. There will be more people to learn about Bitcoin.