Student or Learner
"Curtain rod" in America.
It might be called a "curtain rail" too but the fact that this one is made of wood makes it more likely to be a "curtain pole", to me at least.
In my opinion (in BrE):
Curtain pole: http://www.wilkinsonplus.com/content.../0235720_l.jpg
Curtain rail: http://image.made-in-china.com/2f0j00bvgQOFwcQikn/Curtain-Rod.jpg
Curtain track: http://img.diytrade.com/cdimg/229433...tain_track.jpg
But ordinary people get by without the word!
Also, I tried reversing the translation and put "cornice" into a couple of online translators. They came up with: gzyms, karnes and krajnik. I put "karnisz" into the same translators and both of them said it was "curtain", not "cornice". I also then put "curtain rail" into the translator and it gave "karnisz" as the Polish. Your dictionary definitely has a problem!!
"Karnes"?? This could explain it, but I've never heard this word
I guess the word "karnisz" might have this other meaning, but I never heard it in my whole life. We call the cornice "gzyms". (I have no idea why I'm saying "the cornice", but I believe it's right. Right?)