Parents-in-law in Japanese


I have found three different words meaning _parents-in-law_ :

  * [舅姑]{きゅうこ} 
  * [義父母]{ぎふぼ} 
  * [義理]{ぎり}の[親]{おや}

But I'm sure the words are not interchangeable.

How are the words different? What would be the right way to use each of the
words?




A [corpus](https://pj.ninjal.ac.jp/corpus_center/bccwj/) is a good tool to
answer this type of question yourself.

  * 舅姑: 30 Hits (Many instances are from the same author born before 1960's)
  * 義父母: 50 Hits (Many are from blog articles and chiebukuro questions) 
    * 義母: 758 Hits
    * 義父: 536 Hits
  * 義理の親: 7 Hits 
    * 義理の母: 30 Hits
    * 義理の父: 33 Hits
  * 義親: 20 Hits

IMHO, 舅姑 sounds old, and it may have an unwanted connotation (the kanji 姑 is
often used to refer to bad MIL/DIL relationships, aka 嫁姑問題). If you want a
safe and neutral word, I recommend 義父母 or 義理の親.

