Idda - Idda

Japanese: イッダ - いっだ

...When a person who meets these conditions neglects their obligations, they are socially criticized, so it has become a social security system in Islamic society. A woman who has lost her husband is required to wear white clothes (or black clothes in some places), is forbidden from wearing makeup, and is not allowed to visit anyone other than close relatives during the legally required period of Iddah, that is, four months and ten days after the death of her husband (Quran, Chapter 2, Verse 234). The purpose of this is to clarify whether she is pregnant or not, and, if she is, to clarify the father of the child.

From [Divorce]

...If during this time both parties wish to reconcile, they can always go back to their original state. However, in either case, there is a three-month waiting period during which the wife cannot marry during the 'idda period (three menstrual periods). According to the Quran, Chapter 65, Verses 1 and 4...

*Some of the terminology that mentions "Idda" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…こういう条件の備わっている者がその義務を怠るときには，社会的に非難されるので，イスラム社会における一つの社会保障制度になっている。　夫を失った女性は，法の定めるイッダ期間中，すなわち夫の死後4ヵ月と10日は(コーラン2章234節)，白衣をまとい(所によっては黒衣)，化粧は禁じられ，近親者以外の者を訪問してはならないとされる。妊娠の有無を明らかにすることと，もし妊娠していれば，その子どもの父親を明確にする意味がある。…