dual

Adjective

• a grammatical number category referring to two items or units as opposed to one item (singular) or more than two items (plural)
  • ancient Greek had the dual form but it has merged with the plural form in modern Greek
    

• having more than one decidedly dissimilar aspects or qualities; public preaching and private influence"- R.W.Emerson
  • a double (or dual) role for an actor
    
  • the office of a clergyman is twofold
    
  • every episode has its double and treble meaning-Frederick Harrison
    

• consisting of or involving two parts or components usually in pairs
  • an egg with a double yolk
    
  • a double (binary) star
    
  • double doors
    
  • dual controls for pilot and copilot
    
  • duple (or double) time consists of two (or a multiple of two) beats to a measure
    

Related words

• Synonyms: 
  double , twofold , two-fold , treble , threefold , three-fold , duple