cover one's tracks
cover up one's tracks
To hide and not leave anything, especially foot marks, to show where you have been, so that no one can follow you.
The deer covered his tracks by running in a stream.
To hide or not say where you have been or what you have done; not tell why you do something or what you plan to do.
The boys covered their tracks when they went swimming by saying that they were going for a walk.
cover up
To hide something wrong or bad from attention.
The spy covered up his picture-taking by pretending to be just a tourist.
A crooked banker tried to cover up his stealing some of the bank's money by starting a fire to destroy the records.
The office worker tried to cover up his crimes, but everyone knew that he had been stealing office supplies all along.
In boxing: To guard your head and body with your gloves, arms, and shoulders.
Jimmy's father told him to cover up and protect his chin when he boxed.
To protect someone else from blame or punishment; protect someone with a lie or alibi. Often used with for.
The teacher wanted to know who broke the window and told the boys not to try to cover up for anyone.
The burglar's friend covered up for him by saying that he was at his home when the robbery occurred.