Definition of armageddons:
(n) :
(by extension) Any end of the world, especially by way of a cataclysmic battle or something analogous to one.
(n) :
(by extension) The battle itself.
(n) :
(Christianity, Islam) Mount Megiddo, the site of a prophesied final battle between the forces of good and evil.
(n) :
The scene of a decisive conflict on a great scale.
(n) :
Any great and crucial conflict.
(n) :
(chess) A type of game, usually played when a match would otherwise end in a draw, where black wins drawn games and white is given more time as compensation.