The wind knocked the tree over last night. Bam! It nearly scared me to death.
We all looked up from the maps, silent, and listened to the hurried footsteps in the entryway. They padded up the red carpet, bam-bam-bam, and across the landing and then up the next flight at a gallop, bam-bam-bam. 2007, Joe Biden, Promises to Keep, New York: Random House, published 2008, →ISBN, →LCCN, →OCLC, page 266:
Representing a sudden or abrupt occurrence.
She said she dumped him. Now — bam! — they're back together.
(archaic, slang) To impose on (someone) by a falsehood; to cheat.
This is some conspiracy, I suppose, to bam, to chouse me out of my money 1774, Samuel Foote, The Cozeners:
I’ll break a lamp, bully a constable, bam a justice, or bilk a boxkeeper with any man in the liberties of Westminster. 1747, David Garrick, Miss in Her Teens: or the Medley of Lovers, Act II, in The Plays of David Garrick: A Complete Collection of the Social Satires, French Adaptations, Pantomimes, Christmas and Musical Plays, Preludes, Interludes, and Burlesques, ed. Harry William Pedicord and Fredrick Louis Bergmann, vol. 1 (Carbondale, IL: Southern Illinois University Press, 1980), 93