Croatian: fjaka

[polskajason]

I understand this is borrowed from the Italian fiacca, so maybe it doesn't decline, but how would you express that someone is "on fjaka" (na fjaci?). I've read it referred to this way when translated into English, but don't know the original Croatian.

How else is it typically used?

 

[onitamo]

Fjaka je stanje uma i tijela kad čovjek ne teži ničemu.
To nije lijenost.. nego uzvišeno stanje uma i tijela, kad samo jesi.. to treba doživjeti.
uhvatila me fjaka