Bite the bullet
I have to bite the ballet at this moment. Otherwise, the project will be failed!
The meaning is to accept something difficult and try to live with it. Is it also a kind of slang? I didn't know. It is said that the idiom is derived historically from the practice of having a patient clench a bullet in his or her teeth as a way to cope with the extreme pain of a surgical procedure without anesthetic. OMG...
Refs
idiom, 13-12-13 19:16, 13-12-13 19:16, Yosei