century-old

the compound adjective "century-old" is a modern english formation that transparently combines two native elements to denote great age. the first element, "century," originates from the latin "centuria," a military and political division, itself derived from "centum," the proto-indo-European root for "hundred." the second element, "old," descends from the old english "eald," from the proto-germanic "aldaz," meaning "grown up" or "aged." the logic of the compound is direct and literal, fusing the concept of a hundred-year period with the state of being aged to create a term that precisely signifies something having existed for a century or more, often implying tradition and historical continuity.

Structure: century (hundred) + old (aged) century (from latin 'centuria', from 'centum' meaning hundred; denotes a period of one hundred years) + old (from old english 'eald', meaning aged or of long duration; adjective-forming root).