firn (n.) Look up firn at Dictionary.com
"consolidated snow, the raw material of glaciers," 1853, 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-/*for- (see first).

The only English relic of a useful word meaning "of last year" that was widespread in Indo-European languages. Middle English retained fern "long ago, formerly, of old," fern-days "days of old, former year, a year past." It has cognates in Lithuanian pernai "last year" (adv.), Greek perysi "a year ago, last year," Sanskrit parut "of last year." Also German Firnewein "wine of last year."