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1. sign
   Pronunciation: \ˈsīn\
   Function: noun
   1 a: a motion or gesture by which a thought is expressed or a command or wishmade known b: signal c: a fundamental linguistic unit that designates an object or relation or has a purely syntactic function d: one of a set of gestures used to represent language ; also : sign language
   2 a mark having a conventional meaning and used in place of or to represent a complex notion