cognoscente
Someone possessing superior or specialized knowledge in a particular field.
He is the painter who has been held to combine the most complete grace of form with sublimity of expression. Such at least I have gathered to be the opinion of cognoscenti.
Where it comes from
From obsolete Italian cognoscente (modern Italian conoscente) from Latin cognōscere (“to know”).
Adapted from the Wiktionary entry cognoscente (CC BY-SA 4.0).