I have read several definitions of だって but none of them seem to make sense
when I see it at the beginning of a sentence and I read the context. I saw one
example Japanese sentence and in the English translation だって wasn't translated
into anything.

So what is だって when it's at the beginning of a sentence?
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2011-11-04T23:05:05.457
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2011-12-29T05:27:00.527
2011-12-29T05:27:00.527
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question
meaning register copula て-form ellipsis
What is だって when it's at the beginning of a sentence?
Well, since I have no examples to go off of, I'll guess at which type of
scenario you're thinking of. It can mean like "But" or "Well (then)" in a kind
of defensive sort of way. Usually giving a reason for some action. Like
なぜかというと. Ex:

> お皿{さら}のものはみんな食{た}べなさい → Eat everything on your plate.  
>  だってお腹{なか}が一杯{いっぱい}なんだもん → But I'm full!
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2011-11-04T23:20:45.087
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2011-11-05T01:57:11.507
2011-11-05T01:57:11.507
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answer
だって (at the beginning of a sentence!) is always followed by:

  * reason, pretext (because, ...etc.)
  * opposition (but, ...etc.)

So it's not only 'but' or 'like I said'.

It's context dependent and it CAN be translated as because.

_(Context is an emo-schoolgirl-drama.)_

> **山崎くん** ：スマイルぐらいしてよ。なんでオレともう喋らないの？
>
> _At least give me a smile. Why don't you talk to me anymore?_
>
> **リカちゃん** ：だって、「りかちゃんが好きじゃない」って聞いちゃった
>
> _Because I heard you don't like me._
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2011-11-07T14:14:30.547
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2011-11-07T14:14:30.547
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answer