Definition
To be in a dangerous situation from which one cannot disengage, but in which one cannot safely remain.
Origins
Initially attributed to Roman Emperor Tiberius circa year 1 AD by biographer C. Suetonius Tranquillus. United States, 1820, Thomas Jefferson, writing about the institution of slavery and the Missouri Compromise: : "But, as it is, we have the wolf by the ear, and we can neither hold him nor safely let him go. Justice is in one scale, and self-preservation in the other." :: — Thomas Jefferson to John Holmes (discussing slavery and the Missouri question), Monticello, 22 April 1820