(N.B : in this phrase, the word goy'yim is not to be confused with the word goyim).
(literal translation from Victorian-ca. 1840's-1920's- German)
a) beware of non-monotheists and heathens
b) a phrase meaning, often said in a admonishing tone, "beware of immorality or amorality".
mother: Emily, mark my words, this is your first year in high school; apart from all the cool stuff you will learn, there are also, other, darker, more dangerous things that will surround you (...)
Emily (interrupting her mother) : Is achtung a goy'yim the phrase you wanted to use? I know, dad told me yesterday (...)
mother: Emily, stop putting words in the horse's mouth, but, essentially, yes.