A reader asks about the difference between "relations" and "relationship." Editor Kory Stamper answers.
When do you use relations and when do you use relationship? Can I say "I am in relations with him?"
These two words both mean the same thing ("the way in which two or more people, groups, countries, etc., talk to, behave toward, and deal with each other"), and so some of their uses overlap, but they have different connotations. Relations is used in more formal writing and tends to be used more of the interactions between countries or large groups of people ("relations between Iraq and the U.S.," "relations between blacks and whites"). It is also used in constructions like "diplomatic relations" or "international relations." When relations is used of specific people, it is a very formal use that refers to the act of sexual intercourse. It is not correct to say, "I am in relations with him." For that, you would use the word relationship.
Relationship tends to be used more broadly and generally to describe the interactions between specific people or smaller groups of people. When used of specific people, it often can refer to a romantic connection ("I am in a relationship with him") unless another type of relationship is specified ("her relationship with her coworkers", "the parent-child relationship"). Because relationship is more informal than relations, it is not used as much as relations in formal writing about countries or large groups of people, but these uses ("the relationship between Iraq and the U.S.") are not uncommon and are idiomatic.