1. invent, create (imaginary) information.
The ballon hoax may have been made up.
Some people believe that the moon landing was made up.
Jessica’s story is hard to believe. I’m sure she made it up.
2. compensate for something missied or not done by doing extra or equivalent work.
I missed the test. Can I make it up?
I’m sorry, I forgot your birthday. I’ll make it up.
Make up (with) ; re-establish a friendly relationship by admitting guilt.
David has to make up with his wife.
Joe and his wife were very angry with each other, but last night they finally made up with each other.
