اعتكاف
iʿtikāf
Spending days in the mosque in devotion, especially in the last ten days of Ramadan.
What it means
The Quran mentions staying in the mosques in worship (2:187). Aisha reported that the Prophet used to do itikaf in the last ten days of Ramadan until God took his soul, and that his wives did it after him (Sahih al-Bukhari). The one who does it leaves the mosque only for need, and spends the time in prayer, Quran and remembrance, hoping for the Night of Power.