If you separate the wheat from the chaff or separate the grain from the chaff, you decide which things or people in a group are good or necessary, and which are not. The first two rounds of the contest separate the wheat from the chaff. Judges should not forget that when you separate the wheat from the chaff, you should try to keep the wheat. Note: You can use sort or sort out instead of separate. It's up to Wilkinson to sort out the wheat from the chaff and get the team back to the top of the table. Note: You can refer to the good or necessary things or people in a group as wheat or grain, and to the others as chaff. There's so little wheat in all this chaff. Was there rather less grain than chaff? Note: `Chaff' refers to the outer covers of wheat or other cereal which are separated from the grain by a process called winnowing. In the Bible (Matthew 3:12; Luke 3:17), John the Baptist uses the image of someone separating the wheat from the chaff to describe how Jesus will separate those who go to heaven from those who go to hell.