relationship

Etymology

From relation + -ship.

noun

1. Connection or association; the condition of being related.
   But some discussion of the complex relationship between “allohistory” and sf is appropriate here, as the genres overlap in certain ways. Classical allohistory— such as Trevelyan's "What if Napoleon had won the Battle of Waterloo?" and Churchill's "If Lee had not won the Battle of Gettysburg" —is a rigorously consistent thought-experiment in historical causality. 1 February 2011, Istvan Csicsery-Ronay, Jr., The Seven Beauties of Science Fiction, Wesleyan University Press, pages 102–103
2. (mathematics) The links between the x-values and y-values of ordered pairs of numbers especially coordinates.
   Policing the relationship between government and business in a free society is difficult. Businesspeople have every right to lobby governments, and civil servants to take jobs in the private sector. 2013-08-10, Schumpeter, “Cronies and capitols”, in The Economist, volume 408, number 8848
3. Kinship; being related by blood or marriage.
4. A romantic or sexual involvement.
   They have been in a relationship for ten years, but have never married.
   I'm not advocating sexual promiscuity but I think it's possible for a woman to have many kinds of sexual relationships with many men and that shouldn't affect the status of the marriage. March 17 1975, Marian Christy, “Suzy Chaffee, A Liberated Beauty”, in The Lebanon Daily News
   Her most satisfying sexual relationship seemed to be a threesome with Charles Chaplin Jr. and Eddy Robinson Jr., the spurned sons of famous film fathers. April 8 2000, Dorthea Straus, “Oates on Marilyn: Men, drugs, tragedy”, in The Baltimore Sun
5. A way in which two or more people behave and are involved with each other
   I have a good working relationship with my boss.
   “I Love Lisa” opens with one of my favorite underappreciated running jokes from The Simpsons: the passive-aggressive, quietly contentious relationship of radio jocks Bill and Marty, whose mindless happy talk regularly gives way to charged exchanges that betray the simmering resentment and disappointment perpetually lingering just under the surface of their relationship. August 5, 2012, Nathan Rabin, “TV: Review: THE SIMPSONS (CLASSIC): “I Love Lisa” (season 4, episode 15; originally aired 02/11/1993)”, in (Please provide the book title or journal name)
6. (music) The level or degree of affinity between keys, chords and tones.