الباطن
هو اسمٌ من أسماء الله الحسنى، يدل على صفة (الباطنيَّةِ)؛ أي إنه...
A long period of time estimated to be eighty years or more.
"Ahqāb", which is the plural of "huqb" (ages), is the period of time for which the people of Hell will remain in Hellfire. This is stated by Allah, the Exalted, in the Quranic verse: {In which they will remain for ages.} [An-Naba’: 23] Allah, the Exalted, says that they will abide in Hell for "ahqāb", whenever a "huqb" passes, another will follow in a sequence that will last for eternity. Hence, "ahqāb" means extensive periods of time and successive endless "huqb"; whenever one ends another starts, and so on. According to another interpretation, they will remain in a certain type of torment for long periods of time, and then Allah will inflict upon them other types of torment. "Huqb" is a period of time. There are different views about its length; it is said to be forty years, or eighty years with each day thereof like one thousand years, or three hundred years.
"Huqb" (or huqub): ages, epochs, long periods of time. Original meaning denotes withholding, as in "withholding of rain". Its span is eighty years, and others said that it is more.