The phrase cold turkey comes from an earlier phrase, talk turkey, meaning to talk honestly.
So when people go cold turkey, they’re cutting the excuses and getting down to business.
However, the origins of talk turkey are somewhat less clear.
A jokey anecdote, traced to an employee of the U.S. Engineering Department in the early 1800s, is usually given credit as the origin of the phrase:
A white man and a Native American were hunting together and killed a buzzard and a turkey.
When they were finished, the white man tried to fool the Native American, saying, “You take the buzzard and I will take the turkey, or I can take the turkey and you can have the buzzard.”
The Native American responded, undeceived, that the white man had never offered him the turkey with either option:
“You never once talk turkey to me.”