Cognoscente is a noun that refers to a person with specialized knowledge or expertise.
Coming directly from Italian, our word of the day entered the English language in the late 18th century. While it may be used to describe any kind of expert, it is most often used in reference to those whose expertise is in matters related to art or culture. Here’s an example:
Being a cognoscente on wine has made my cousin famous. But somehow I’m still struggling to reach any kind of fame as an expert on 80s sitcoms.