does なんだこれは specifically have a bad connotation?

Question

I heard this and wasn't sure if it had a negative meaning or not. Does the phrase always indicate irritation or not necessarily? I'm a bit confused since some people say it's just an informal tone between friends, and some say it's said due to frustration? Can anyone clarify please? Thanks!

Answer 1

The word order conveys some meaning.

Normally you would say: それはなんですか？

By putting なんだ at the beginning it conveys the idea of surprise (either good or bad). Not being polite-speech also comes up as rougher or more direct (like saying something crudely without thinking about how you say it).

I guess it depends on the tone similarly to the english "what is this?". But surely you got "surprise + informal" for sure.

Answer 2

なんだこれは is not necessarily negative, but it does indicate the speaker is surprised or amazed, like "What the heck is this?".

For one thing, だ is not really a common copula in ordinary informal speech. When it's used, it would sound masculine, blunt, urgent and/or oppressive. For example, you should use the question "誰だ?" only against a highly suspicious person like an intruder.

• を+[する noun] + だ structrure?
• What is the difference between 何だと and 何ですと?
• ~たいだとか why is there a だ here?

For another thing, the reversed word order adds a dramatic feel to it, as pointed by another answer.