Definition of deus ex machinas:
(n) :
(narratology) Any resolution to a story that does not pay due regard to the story's internal logic and that is so unlikely that it challenges suspension of disbelief, and presumably allows the author, director, or developer to end the story in the way that they desired.
(n) :
(by extension) A contrived solution to a problem, relying on an agent external to the situation.
(n) :
(historical, literary) A deity in Greek and Roman drama who was brought in by stage machinery to intervene in a difficult situation (i.e., to resolve a crisis, or untangle issues surrounding it, a character logically expected to do so).
(n) :
(historical) A machine used to bring an actor playing a god onto the stage, either up through a trapdoor or (e.g. by crane) from above.