expression
no matter what; after all; in the end
Casual spoken contraction of 何と言ったって (なんといったって). Used to emphasize that something is true regardless of circumstances, or to give a reason that overrides objections. Often followed by a conclusion or justification.
なんつったって、彼はまだ子供だから、そんなことわかるわけないよ。
After all, he's still a kid, so there's no way he'd understand that.
なんつったって、これが一番安いんだから、これに決めよう。
No matter what, this is the cheapest, so let's go with this one.