Global Nomads is a term coined by Norma McCaig and according to Barbara Shaetti in this article, can be used interchangeably with TCK.
I remember Norma feeling like it was a more descriptive term that avoided the term ‘kids’ and was more encompassing.
Norma also believed that having a childhood experience in at least one country other than your passport country distinguished Global Nomads from persons who experienced living in foreign country after adulthood.