What does the word fallacy mean?

Usage examples for fallacy

  1. I have been so long accustomed to the fallacy of pratique reports, that I do not give entire credit to this. – Memoirs and Correspondence of Admiral Lord de Saumarez, Vol. I by Sir John Ross
  2. But no man understood better than he did the fallacy of the argument that modern abolitionists had put back the cause of emancipation in the South. – Isaac T. Hopper by L. Maria Child