(literal translation from German: beware of non-monotheists): 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 goyim the phrase you wanted to use? yes, i know, dad told me yesterday, when I packed my things.

mother: Emily, stop putting words in the horse's mouth, but yes essentially you are correct.
by Sexydimma January 4, 2014
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