のなんのって

のなんのって says something was so extreme you can hardly describe it: "so hot you wouldn't believe it", "talk about angry". It follows an い-adjective or a plain-form verb, past or non-past, directly; a な-adjective takes な first.

• × 静かのなんのって → 静かなのなんのって

The second half usually shows how far it went: you couldn't solve half the test, you cheered until your voice gave out. It can also be left off, and the sentence ends on のなんのって.

The word in front is usually a feeling or a sensation – heat, pain, fear, anger, surprise – or something the speaker reacts to strongly.

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のなんのって belongs to conversation and chatty writing such as blogs and personal essays. It is out of place in a formal speech or a business email, where you would say ひじょうに非常に or とても instead.