Definition: to make a difficult or painful decision; to take a difficult step
When demand was down, U.S. automakers had to bite the bullet and cut jobs.
I know tonight’s football match is big, but we have to finish this sales presentation. We have to bite the bullet, and work late tonight.
Origin: This idiom comes from the military. During the U.S. Civil War, doctors sometimes ran out of whiskey for killing the pain. A bullet would be put in the wounded soldier’s mouth during surgery. He would “bite the bullet” to distract him from the pain and keep him quiet so the doctor could do his work in peace.