صحيح
ṣaḥīḥ
“Sound”: the highest grade of a hadith, and the title of the two most trusted hadith collections.
What it means
A hadith is sahih if its chain is connected through upright and exact narrators, with no hidden defect. The collections of al-Bukhari (d. 870) and Muslim (d. 875), called the Sahihayn, are regarded as the most reliable books after the Quran. Other grades are hasan (good) and da‘if (weak).