French-Québec : “Kossé ça?”
French also : “C’est quoi?”
… or : “Qu’est-ce?”
Word for word of "qu’est-ce-que c’est ?” …
…goes like : "What’s this that this is?
…or : “What’s this which this is?”
“Qu’est-ce?” sounds like the english “Case”.
Since this is just one syllable it might be difficult to hear out of context. Edit : Delayed 8h because of DDOS attack
I ended up replying to the original comment, but your translation to English made me realize that in Portuguese we commonly say "O que que é isso?" which is basically "qu'est-ce-que c'est?"
In Portuguese we actually can say "O que é isso?", basically the same as in Spanish, but I'd say I use more commonly "O que que é isso?", which seems closer to French version. Funny, had never thought about it like that.
Although most French say "Qu'est-ce que c'est", it is worthy to note that the proper/formal French is "Qu'est-ce?". So strictly equivalent to "What is that", word for word. :)
Then ask someone who hasn't learnt French how many syllables there are in "qu'est-ce que c'est ?" And watch the look of horror on their face when you tell them it's just 3.