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Etymology
There are multiple explanations of the etymology of "cracker", most dating its origin to the 18th century or earlier. One theory holds that slave foremen in the antebellum South used bullwhips to discipline African slaves, with such use of the whip being described as 'cracking the whip'. The white foremen who cracked these whips thus became known as "crackers".[3][4][5][6]
They are called by the town's-people, "Crackers," from the frequency with which they crack their large whips, as if they derived a peculiar pleasure from the sound"[7]
'A cracker cowboy' with his Florida Cracker Horse and dog by Frederick Remington, 1895
Another whip-derived theory is based on Florida's "cracker cowboys" of the 19th and early 20th centuries; distinct from the Spanish vaquero and the Western cowboy. Cracker cowboys did not use lassos to herd or capture cattle. Their primary tools were cow whips and dogs.[8][citation needed]
Yet another whip-derived theory traces this term from Middle English word "cnac" or "craic" which originally meant the sound of a cracking whip, but came to refer to any loud noise. In Elizabethan times this could refer to "entertaining conversation" (one may be said to "crack" a joke) and could be used to describe loud braggarts; this term and the Gaelic spelling craic are still in use in Ireland, Scotland and Northern England. It is documented in Shakespeare's King John (1595): "What cracker is this same that deafs our ears with this abundance of superfluous breath?"[9][10]
An alternative theory holds that the term comes from the common diet of poor whites. The 1911 edition of Encyclopedia Britannica supposes that the term derives from the cracked (kernels of) corn which formed the staple food of this class of people.[11]