15 letters · 26 points in Scrabble
noun a relation between two opposite states or principles that together exhaust the possibilities
noun the interrelation of reciprocity whereby one thing supplements or depends on the other
originEtymology tree English complementary Proto-Indo-European *-teh₂ Proto-Indo-European *-ts Proto-Indo-European *-teh₂ts Latin -itāsder. Old French -itebor. Middle English -ite English -ity English complementarity From complementary + -ity.
Etymology from Wiktionary, CC BY-SA 3.0