Nachas, or alternately, nachus, is an english
spelling of a yiddish
word that means "pleasure
". It is most often used, in english, in the phrase, "shepping nachus".
To "shep" nachas, means to derive pleasure from something. Although, quite obviously, the verb shep is not actually conjugated this way in yiddish
Ex: "Grandma Cohen is shepping nachas for her grandson's Bar Mitzvah"
This, along with several other yidish words and phrases, is part of a growing dialect among Americans with Jewish heritage.
Nachas is similar to another commonly used yiddish word kvell. Both signify positive emotional feelings
Mike Meyers' character Linda Richman on Saturday Night Live's "Coffee Talk" sketch is probably the most popular example of this American linguistic phenomenon. It should be known, however, that some of the words he uses on that show are not authentic.