الوتر
كلمة (الوِتر) في اللغة صفة مشبهة باسم الفاعل، ومعناها الفرد،...
Optimal divorce is when a man divorces his wife once while she is in a state of purity in which he has not had sexual intercourse with her until her waiting period ends.
"Ahsan at-talāq" (optimal divorce) is that a man divorces his wife once while she is in a state of purity (i.e. not during her monthly menses) in which he has not had sexual relations with her, and this state continues until her "‘iddah" (post-divorce waiting period) expires.
This is when a man divorces his wife at a time when she is not in her period, having not had intercourse with her after her last period, and maintaining her until her waiting period is over.