snake oil

WordReference Random House Unabridged Dictionary of American English © 2025

snake′ oil′, 

1. any of various liquid concoctions of questionable medical value sold as an all-purpose curative, esp. by traveling hucksters.
2. Slang Terms deceptive talk or actions;
   hooey;
   bunkum:
   The governor promised to lower taxes, but it was the same old snake oil.
• 1925–30, American.
snake′-oil′, adj.