chapter (of the Quran)
Feminine noun. Plural: سُوَرٌ (suwar). The Quran has 114 surahs. Etymology debated: from سُور (wall/enclosure) or from the Syriac.
Each surah is a self-contained unit with its own theme. The longest is al-Baqarah (286 verses); the shortest is al-Kawthar (3 verses).