dual Meaning, Definition & Usage

1. adjective satellite consisting of or involving two parts or components usually in pairs
   double; duple.
   
   • 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
2. adjective satellite having more than one decidedly dissimilar aspects or qualities; public preaching and private influence"- R.W.Emerson
   treble; twofold; two-fold; double; three-fold; threefold.
   
   • 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
3. adjective satellite 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

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