Talk turkey
(See: Tell somebody flat out)
Origin
The English newspaper The Daily Express explained that for an
English audience in a January 1928 edition: "She talked cold turkey
about sex. Cold turkey means plain truth in America."
There are many uses of the term in U.S. citations from the early 20th century. For example, this from The Oakland Tribune, August 1915: "This letter talks cold turkey. It gets down to brass."
There are many uses of the term in U.S. citations from the early 20th century. For example, this from The Oakland Tribune, August 1915: "This letter talks cold turkey. It gets down to brass."