complementarity

Noun

complementarity (countable and uncountable, plural complementarities)

1. The state or characteristic of being complementary.
   • "Synergy is one of the most overused words in the English language, but there is a tremendous complementarity to these organizations."1987 April 2, Kenneth N. Gilpin, “2 Forecasting Firms to Merge”, in New York Times, retrieved 01 Apr 2014
2. A semantic relationship between two words wherein negative use of one entails the affirmative of the other with no gradability; the relation of binary antonyms.
   • For complementarity, there are entailments both from affirmative sentences to the corresponding negative sentences (which is what ordinary antonymy allows) and from negative sentences to the corresponding affirmative sentences. [...] That light is on entails That light is not off. That light is not...2005, Andrew John Merrison, Aileen Bloomer, Patrick Griffiths, Christopher J. Hall, Introducing Language in Use, London: Routledge, →ISBN, page 112
3. The idea that physical phenomena may have (mutually contradictory) properties that cannot be observed simultaneously (e.g. wave-particle duality).