"bristly fibers on grain of plants," c.1300, from Old Norse ögn, from Proto-Germanic *agano (cf. Old English egenu, Old High German agana, German Ahne, Gothic ahana), from PIE *ak-ona- (cf. Sanskrit asani- "arrowhead," Greek akhne "husk of wheat," Latin acus "chaff," Lithuanian akuotas "beard, awn"); suffixed form of PIE root *ak- "sharp" (see acrid).