Gloves used to have a number for the size .Mine is size 9 what now is large. But it's difficult because gloves come from many places and sizes can be weird !!
I once returned a pair of gloves to LLBean because of that -the insulated gloves were made in Indonesia !!
Peoples' hands can vary greatly too . I helped a shooter design grips for his revolver .His hand was as big as mine but his fingers were a full 1/2" longer than mine !