Surah (sometimes spelt sura or surat سورة (sūrah), plural suwar سور) is an Arabic term that literally means "something enclosed or surrounded by a fence or wall."
A surah is a "chapter" of the Qur'an. They are traditionally ordered in order of length and begin with the shortest. Each surah is named for a word or name mentioned in an ayah (section), of that 'surah'.