なんでやねん

expression, interjection

what the hell?; you've got to be kidding!

Kansai dialect phrase used as a strong, humorous retort expressing disbelief, exasperation, or calling out nonsense. Often associated with tsukkomi in manzai comedy.

• 「明日あしたから宇う宙ちゅうに行いくねん」「なんでやねん！」

  "I'm going to space tomorrow." "What the hell?!"

• そんなわけないやろ、なんでやねん。

  There's no way that's true—you've got to be kidding.