expression
speaking of ...; as for ...
Follows a noun to introduce a topic emphatically, often with a sense of admiration, surprise, or strong assertion. Common in formal or rhetorical speech.
彼の演技たるや、まさに圧巻だった。
Speaking of his performance, it was truly magnificent.
その景色たるや、言葉にできないほど美しかった。
As for that scenery, it was so beautiful that words could not describe it.