It is the official name, after Greece blocked "Macedonia" from the start. The two countries had a major disagreement about the name which was finally sorted by this. For those reasons, the country was called FYROM (Former Yugoslav Republic of Macedonia) for quite a while.
The main reason being that Greece – for some weird, unfathomable reason – feared that the name "Macedonia" would inherently mean that the other country would claim the Greek region of Macedonia (i.e. South Macedonia in your book).
Great quiz; really got me to think hard!
The main reason being that Greece – for some weird, unfathomable reason – feared that the name "Macedonia" would inherently mean that the other country would claim the Greek region of Macedonia (i.e. South Macedonia in your book).