noun
mutual mourning
Refers to a situation where two parties are both in mourning, and according to custom, they refrain from exchanging condolence calls or offering help to each other. This is a specialized term related to Japanese funeral etiquette.
相悔みの間は、お互いに弔問を控えるのがしきたりです。
During mutual mourning, it is customary to refrain from making condolence calls to each other.
悔み means 'condolence' or 'mourning' in general, while 相悔み specifically refers to the mutual state of mourning between two parties.
Compound of 相 (あい, mutual) and 悔み (くやみ, mourning). The exact historical origin is uncertain, but it follows a common pattern of forming nouns with 相- to indicate reciprocity.