adverb
where?
Emphatic interrogative, stronger than どこ. Often used in rhetorical questions or when demanding an answer.
こんな時間にどこだって行くの?
Where on earth are you going at this hour?
どこだってそんな話を聞いたの?
Where did you hear a story like that?
adverb
Emphatic 'anywhere', similar to どこでも but with a stronger, more colloquial tone. Often used in affirmative statements.
See also: 何処でも (どこでも)
お金さえあれば、どこだって行けるよ。
As long as you have money, you can go anywhere.
彼はどこだって寝られる人だ。
He's the kind of person who can sleep anywhere.