Source : Webster's Revised Unabridged Dictionary (1913)

Bam \Bam\ (b[a^]m), n. [Prob. a contr. of bamboozle.]
   An imposition; a cheat; a hoax. --Garrick.

         To relieve the tedium, he kept plying them with all
         manner of bams.                          --Prof.
                                                  Wilson.

Bam \Bam\, v. t.
   To cheat; to wheedle. [Slang] --Foote.