القاهر
كلمة (القاهر) في اللغة اسم فاعل من القهر، ومعناه الإجبار،...
Imrān ibn Husayn (may Allah be pleased with him) reported that he was suffering from hemorrhoids (piles), so he asked the Prophet (may Allah's peace and blessings be upon him) about the prayer and he said: "Pray standing; if you cannot, then sitting; if you cannot, then lying on your side."
شرح الحديث :
This noble Hadīth explains the manner of praying for the person having hemorrhoids, suffering a pain when standing, or having similar excuses. The Prophet (may Allah's peace and blessings be upon him) stated that prayer by default is offered in a standing position. However, if the person is unable to stand, he should pray sitting. If one is not able to pray sitting, then he may pray lying on his side.