it usually refers to speaking frankly, discussing hard facts, or getting down to serious business.
larry-"i'm not to sure if i want buy the ring for 2,500 cuz it has flaws"
tim-"there are no flaws in it, i had it checked myself"
larry-"well i seen better rings by another client"
tim-"lets talk turkey, the watch and ring for 6,000"
tim-"NOW WE'RE GETTING SOME WHERE"