NAFPS Forum

https://rationalwiki.org/wiki/PIDOOMA — (I quote the beginning of this funny post):

QuotePIDOOMA (the acronym for Pulled It Directly Out Of My Ass. or argumentum ex culo) ("argument from the asshole") is the act of arguing by way of flinging everything at the wall and seeing what sticks ad hoc bullshit in a desperate attempt to shore up a blatantly untenable argument.

As a general rule, if something stinks about the argument, there's a good chance it's an argumentum ex culo.