grisly adj.

ghrēi-, Proto-Indo-European root meaning "to rub." 

It forms all or part of: chrism; Christ; christen; Christian; Christmas; cream; grime; grisly; Kriss Kringle.

It is the hypothetical source of/evidence for its existence is provided by: Greek khriein "to anoint, besmear;" Lithuanian grieju, grieti "to skim the cream off;" Old English grima "mask, helmet, ghost," Middle Low German greme "dirt."

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.

"somewhat gray," 1590s, from grizzle "gray-colored" + -y (1). Also see grizzled. Grizzly bear (ursus horribilis) for the large ferocious bear of the western U.S., is recorded by 1806; sometimes said to belong rather to grisly (q.v.), but either adjective suits it.