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monosemy

British  
/ ˈmɒnəʊˌsiːmɪ /

noun

  1. the fact of having only a single meaning; absence of ambiguity in a word Compare polysemy

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of monosemy

C20: from mono- + ( poly ) semy