Cold snap/spell
A sudden short period of cold weather. The cold snap lasted for five days.
Come down hard on (someone)
To scold or punish someone severely. The police are coming down hard on drunk drivers now.
Clean bill of health
The assurance that an animal or person is healthy. The astronaut was given a clean bill of health before he began training.
Clean out (someone) or clean (someone) out
To rob someone of almost everything, to steal almost everything from someone. The robber enterd the store at night and cleaned out the owners.
Coat and tie
A jacket or a sports coat and a necktie. The company asked everyone to wear a coat and tie to the company dinner.
Come down in the world
To lose one's social position. My father came down in the world when he decided to change jobs.
The coast is clear
No danger is in sight, no one can see you. When the coast is clear we will try to enter the building.
Clue (someone) in or clue in (someone)
To inform someone about something. We tried to clue the principal in about why the students were absent.
Clean out (something) or clean (something) out
To empty something, to tidy something by removing something. We spent the day trying to clean out our garage.
Chicken feed
A small amount of money. The man sold his car for chicken feed.