1
general::
Phrase(s): hang in the balance
Go to in the balance.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Be in a precarious condition or in a state of suspense. For example, The doctor said her life was hanging in the balance. This expression alludes to the suspended balance scale where an object is placed in one pan and weights are added one by one to the other pan until the two are balanced. [First half of 1400s]
American Heritage Idioms