Rudi:

Talk Turkey: Speak frankly or bluntly.

The origin of this phrase, as I understand it, comes from a story about a native american dealing with a eurpoean settler in the "new world." The european and the native american were out for a day of hunting together and at the end of the day had bagged a turkey and a dove. They couldn't decide how to divide the spoils so the european suggested:
"I'll flip a coin. If it's tails I get the turkey. If its heads, you get the dove."
To which the (smarter than he looked) native american replied:
"Never once did you talk turkey to me."