Gentile — A member of a nation-family, in the Latin "gentilis", in the Greek "ethnikos", in the Hebrew "goy". Each society taught that members of its own nation (or family) were normal civilised people, "gentle", "gentlemanly", but members of nations (in general) were outsiders, foreigners, with languages that were "barbaric".
Seen in Genesis 12:2 when God tells Abraham he would make of him a great nation or "goy" גּוֹי . Then, in Acts when Paul explained how God had told him to Go, for I will send you far away from here to the "goyim" גּוֹיִים , his inferred rejection of Israel and acceptance of "barbarians" brought a wild reaction from the listeners. Acts 22:21.