OSO
 n.— «“Polyamory is never having to say you’ve broken up,’’ said Sally Amsbury of Oakland, whose sex and love life openly includes her husband and two “other significant others,” known in polyamory parlance as “OSOs.”» —“Committed to marriage for the masses Polyamorists say they relate honestly to multiple partners” by Don Lattin San Francisco Chronicle (California) Apr. 20, 2004. (source: Double-Tongued Dictionary)