「何だって?」(Nani da tte?) means "What did you say this is?", while 「何って?」(Nan tte?) means "What did you say?". There are diferences in the meaning and in the reading.
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「何だって?」(Nani da tte?) means
「何だって?」(Nani da tte?) means "What did you say this is?", while 「何って?」(Nan tte?) means "What did you say?". There are diferences in the meaning and in the reading.