Goyish

[Justin Bieber]

Adjective, referring to something or someone who is [not Jewish]. Derived from [goy] - a Hebrew word used in the Jewish [Scriptures] (a.k.a. the Old Testament). The word means nation, and is always used within these [scriptures] to refer to the nations of the world. Significantly, within the Old Testament, [Judah] (the Jewish nation) itself is called a goy.
In the Old Testament, the Jews were called to be a nation separate from the other nations, which were all Pagan. And so, colloquially, all non-Jewish nations came to be called [goyim] as in the nations from which the God of the Old Testament had called upon the Jews to separate themselves.
A word used by some Jews to refer to the things of the [Gentiles] (non-Jews), whether ideas or cultural manifestations, etc. The word can have derogatory connotations, such as the word black when used to refer to a persons of African descent. It can be neutral or negative depending on the context and the intent of the speaker.

Noun: goy
Pl. Noun: goyim
Adjective: goyish or, less commonly, goyisch