プログレッシブ和英中辞典(第4版)の解説
わけしり【訳知り】
彼は訳知りだ
〔世の中に通じている人〕He is a man of the world./〔情事に通じている人〕He understands what it is to be in love.
訳知り顔に色の道のことを言う
He talks as if he were well-versed in matters of love.
訳知り顔に物を言う
He talks as if he knew [knows] everything about it [the matter].(▼knewは実際に分かっていない場合)