bull butter

noun2

1. •
   (slang, euphemistic) bullshit

   • (for you city folks, bull butter is that black, smelly substance found in piles all over cow pastures) but in your case, the bull butter ain't on the outside. — 2014
2. •
   (disapproving, old-fashioned) margarine

   • About one-third of this importation was margarine, which in America was called "bull butter." — 1892