Are Dothraki really a race?

Why do we consider dothraki a race? I mean if you compare a random dothraki man or woman with a random Slaver's Bay man or woman - you won't be able to tell who is who (providing that they wear the same type of clothing, hair style etc). Many minor dothraki characters (I don't mean khals or other significant dothraki characters) are portrayed by white Caucasian people and could be easily mistaken for people from Westeros. So I personally don't really see dothraki as a race, because if it is race - what defines this race? Is it skin color? Shape of skull? Whatever? 01:06, September 3, 2016 (UTC)