يسر
Yusr
That which is possible without hardship; ease
What it means
Yusr means ease: what a person can do without hardship. The Quran says “Allah intends ease for you and does not intend hardship” (2:185) and “with hardship comes ease” (94:5-6). Another verse promises that Allah will bring ease after hardship (65:7). The principle shapes the law. Jurists hold that hardship calls for relief, and the sharia allows concessions: the traveller may shorten the prayer, and the sick and the traveller may postpone the fast. A saying of the Prophet (peace be upon him) in Sahih al-Bukhari states that the religion is ease. The word ʿusr, hardship, is its opposite.
Often misunderstood as
That ease means laxity, when it is a stated principle of the law with defined concessions.
Term and Arabic as listed in Ismail al Faruqi, Toward Islamic English (International Institute of Islamic Thought, 1995), p. 47, listed as YUSR. The definition is restated here.