Eli5: What determines if a nationality ends with -ese (chinese, japanese…), -an (Ghanian, Egyptian, American) or just the county itself (Thai)?

Question

Eli5: What determines if a nationality ends with -ese (chinese, japanese…), -an (Ghanian, Egyptian, American) or just the county itself (Thai)?

In: 4879

Answer 1

There is no recognizable rule for the normal language user. They only have a phonotactic feeling – and lexical knowledge. Derivation does not follow specific, strict rules – in every language. It has a set of affixes which can sometimes be applied on the same word or stem or root which also proves that it is not merely a matter of morphonology, but at best of phonotactic restrictions. Country names are foreign words, therefore often disrespect the syllable structure of the language using this word as a morphological base, and so, restrictions arise, and alternatives are preferred.