centuries-long

the compound adjective "centuries-long" is a modern english formation that follows a productive pattern for indicating duration. the first element, "centuries," derives from the latin 'centuria,' which originally denoted a group of one hundred soldiers or a division of land, but in late latin came to signify a period of one hundred years. the second element, "long," originates from the proto-germanic langaz, meaning having great linear extent or duration, which evolved into the old english 'lang.' the compound logically combines these elements to denote an event or state whose duration is measured on the scale of multiple hundred-year periods, projecting a sense of immense historical or future span.

Structure: centuries (noun) + long (adjective) centuries (from latin 'centuria', meaning a group of one hundred, specifically a period of one hundred years); long (from old english 'lang', meaning having great duration or extent)