that the Slovak word "hovorca" can cause some problems but it is probably not so straightforward as some of you indicate it is. Yes, on its own it means "a spokesperson" but certainly not in connection with "native - rodený" or "of Slovak language". This just makes a huge difference. Just google "rodený hovorca" and you will see thousands of links. For example:
Rodený hovorca španielčiny
Hľadáme rodeného hovorcu španielčiny na externú spoluprácu
We are looking for a native speaker of Spanish for...
http://www.megainzercia.sk/index.php?action=show&id=63519780...And guess who uses "rodený hovorca" most? Translators, translation and localisation companies, teachers of languages etc. Just google it.