Quiz: Remember the definition of mal de mer?
late 14c., "nearness in relation, kinship," later also "physical nearness" (early 15c.), from Old French propinquite (13c.) and directly from Latin propinquitatem (nominative propinquitas) "nearness, vicinity; relationship, affinity," from propinquus "near, neighboring," from prope "near" (enlarged from PIE *pro "before;" see pro-) + suffix -inquus.
Nothing propinks like propinquity [Ian Fleming, chapter heading, "Diamonds are Forever," 1956; phrase popularized 1960s by U.S. diplomat George Ball]