﴿ إِذَا تُتْلَىٰ عَلَيْهِ ءَايَٰتُنَا قَالَ أَسَٰطِيرُ ٱلْأَوَّلِينَ ﴾

“[and so,] whenever Our messages are conveyed to them, they but say, "Fables of ancient times!"”

Literally ‘A prison’. It means a certain place in which the record of the deeds of the wicked is preserved.