noun
man of the world; connoisseur; well-informed person
Refers to someone sophisticated, knowledgeable about worldly pleasures, arts, or social affairs. Often carries a nuance of refined taste and experience, sometimes with a hint of dilettantism.
彼は食通で、都内の隠れた名店をよく知っている通人だ。
He is a food connoisseur and a man of the world who knows many hidden gem restaurants in Tokyo.
あの人は芸術にも詳しい通人だから、展覧
That person is a well-informed connoisseur of art, so his way of choosing exhibitions is different.
Composed of 通 (つう, 'pass through, well-versed') and 人 (じん, 'person'). The exact historical derivation is uncertain, but the combination naturally yields the meaning of a person who is well-versed in worldly affairs.