يا أرحم الراحمين
Yā Arḥama’l-Rāḥimīn
O Most Merciful of those who show mercy; said in any need of help
What it means
This is an invocation of Allah, meaning “O Most Merciful of those who show mercy”. Muslims say it when they need help, in illness, distress, fear or ordinary requests. The phrase comes from the Quran, where Moses prays “You are the Most Merciful of the merciful” (7:151) and Job calls on his Lord with the same words (21:83). The superlative places Allah’s mercy above that of every human being. People say the phrase aloud or silently, singly or as part of a longer supplication, and it often accompanies other names of Allah. It is a form of duʿāʾ, an address to Allah, and needs no special occasion or place.
Often misunderstood as
That it can be reduced to “O Merciful”, which loses the superlative above all who show mercy.
Term and Arabic as listed in Ismail al Faruqi, Toward Islamic English (International Institute of Islamic Thought, 1995), p. 59, listed as YĀ ARḤAM AL RĀḤIMĪN.. The definition is restated here.