firn (n.)

"consolidated snow, the raw material of glaciers," 1839, literally "last year's snow, névé," from German Firn, from Swiss dialectal firn "of last year," from Middle High German virne "old," from Old High German firni, related to Old English fyrn "old," Gothic fairns "of last year," from Proto-Germanic *fur- "before" (see fore (adv.)).

The only living English relic of a useful word meaning "of last year" that was widespread in Indo-European languages (cognates: Lithuanian pernai "last year" (adv.), Greek perysi "a year ago, last year," Sanskrit parut "of last year;" also German Firnewein "wine of last year"). Old English had fyrngemynd "ancient history," more literally, "memory of long ago;" fyrnmann "man of old times;" fyrnnes "antiquity;" fyrnsægen "old saying." Middle English retained fern "long ago, formerly, of old," fern-days "days of old, former year, a year past."