What does nda ンだ stand for?


[![enter image description
here](https://i.stack.imgur.com/OIc0v.jpg)](https://i.stack.imgur.com/OIc0v.jpg)

I know that kore means “this” but i didn’t understand what does this
sentence/word means i also didn’t know what is the meaning of nda




@chargestriker is correct, it's a shortened form of なんだ, so the whole sentence
would be なんだこれ？ or なんだ、これは？ ... essentially "What's this?" or colloquially
"What the heck is this?" ...we do the same in English, with many people
shortening the question to "The heck is this??"

