Im·pos·si·ble a.  Not possible; incapable of being done, of existing, etc.; unattainable in the nature of things, or by means at command; insuperably difficult under the circumstances; absurd or impracticable; not feasible.
     With men this is impossible; but with God all things are possible.   --Matt. xix. 26.
     Without faith it is impossible to please him.   --Heb. xi. 6.
  Impossible quantity Math., an imaginary quantity. See Imaginary.
  Syn: -- See Impracticable.