Confront unpleasantness, especially the consequences of one's errors. For example, When the check bounced, he had to face the music. The precise allusion in this expression has been lost. Most authorities believe it refers to a theater's pit orchestra, which an actor must face when he faces what can be a hostile audience, but some hold it comes from the military, where a formal dismissal in disgrace would be accompanied by band music. [Second half of 1800s] Also see face up to.

To accept unpleasant consequences: “After several years of cheating his employer, the embezzler finally had to face the music.”