A bread roll?
It’s just a tiny, baked individual portion of a completely ordinary and unadulterated bread dough. Same mix as for loaves.
It isn’t enriched with eggs, fruit, sugar, fat, seeds or other stuff. That would allow it to have endless different names and regional variations.
It’s just (small) bread, piled in baskets in cafeterias, served at tables in restaurants and standard fare.
Anything else, other names which are legion, can only be due to different recipes or just wonderful, regional names.
A bread roll, whatever its shape, is just that. One’s own portion of the staff of life.