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.
- Incapable of having existence or of occurring.
- Not capable of being accomplished: an impossible goal.
- Unacceptable; intolerable: impossible behavior.
- Extremely difficult to deal with or tolerate: an impossible child; an impossible situation.