1
general::
In trouble or an awkward position, out of luck, as in His check bounced, leaving Jim behind the eight ball with his landlord. The term comes from pocket billiards or pool, where in certain games if the number eight ball is between the "cue ball" and "object ball" the player cannot make a straight shot. [Colloquial; c. 1920]
American Heritage Idioms
2
general::
Phrase(s): *behind the eight ball
1. Fig. in trouble; in a weak or losing position. (Alludes to the eight ball in pool, which in certain games cannot be touched without penalty. *Typically: be ~; get ~; have someone ~; put someone ~.) • I’m behind the eight ball again and can’t see how to relieve my dilemma. • John is behind the eight ball because he started writing his term paper far too late. 2. Fig. broke. • Sorry, I’m really behind the eight ball this month. I can’t make a contribution. (*Typically: be ~; get ~; have someone ~; put someone ~.) • I was behind the eight ball again and couldn’t make my car payment.
McGrawhill's American Idioms And Phrasal Verbs