alternative

Adjective

• pertaining to unconventional choices
  • an alternative life style
    

• necessitating a choice between mutually exclusive possibilities
  • alternative possibilities were neutrality or war
    

• serving or used in place of another
  • an alternative plan
    

Noun

• one of a number of things from which only one can be chosen
  • what option did I have?
    
  • there no other alternative
    
  • my only choice is to refuse
    

Related words

• Synonyms: 
  alternate , substitute , option , choice