simmer down
To become less angry or excited; become calmer.
Tom got mad, but soon simmered down.
sit down
take a seat
To sit on a seat or resting place.
After gym class Jim was tired and was glad to sit down and rest.
We sat down on the park bench and watched the children play.
There aren't any more chairs, but you can take a seat on the floor.
slap down
To stop (someone, usually in a lower position or job) from doing or saying something, in a rough way or with a scolding; silence.
When Billy talked back, the teacher slapped him down.
To put a quick stop to; refuse roughly.
The boss slapped down our idea of taking a nap on the job every afternoon.
slow down
To go more slowly than usual.
The road was slippery, so Mr. Jones slowed down the car.
Pat once could run a mile in five minutes, but now that he's older he's slowing down.
The car was going so fast that the motorist couldn’t slow it down enough to make the sharp curve.
You’re eating too fast to digest your food well. Slow down!
slowdown
A period of lesser activity, usually in the economic sphere.
We all hope the current slowdown in the economy will soon be over.
smooth down
To make calm; calm down.
Mrs. Smith's feelings were hurt and we couldn't smooth her down.
step down
To come down in one move from a higher position to a lower.
As soon as the train stopped, the conductor stepped down to help the passengers off.
To make go slower little by little.
The train was approaching the station, so the engineer stepped it down.
To leave a job as an official or some other important position.
When the judge became ill, he had to step down.
Next May the principal will step down after thirty-five years of service to the school.
The angry shareholders wanted the company president to step down because of the stock scandal.
take down a notch
take down a peg
To make (someone) less proud or sure of himself.
The team was feeling proud of its record, but last week the boys were taken down a peg by a bad defeat.