gruesome (adj.)

1560s, with -some (1) + grue, from Middle English gruen "feel horror, shudder" (c. 1300); not recorded in Old English or Norse, possibly from Middle Dutch gruwen or Middle Low German gruwen "shudder with fear" (compare German grausam "cruel"), or from a Scandinavian source (such as Danish grusom "cruel," grue "to dread," though others hold that these are Low German loan-words). One of the many Scottish words popularized in England by Scott's novels. Related: Gruesomely; gruesomeness.