1560s, "wild, unruly" (originally in reference to hawks), from Middle French haggard, probably from Old French faulcon hagard "wild falcon," literally "falcon of the woods," from hagard, hagart, from Middle High German hag "hedge, copse, wood," from Proto-Germanic *hagon, from PIE root *kagh- "to catch, seize;" also "wickerwork, fence" (see hedge (n.)). OED, however, finds this derivation "very doubtful." Sense perhaps reinforced by Low German hager "gaunt, haggard." Sense of "with a haunted and wild expression" first recorded 1690s; that of "careworn" first recorded 1853. Sense influenced by association with hag. Related: Haggardly; haggardness.