Grim

# S: (adj) grim, inexorable, relentless, stern, unappeasable, unforgiving, unrelenting (not to be placated or appeased or moved by entreaty) "grim determination"; "grim necessity"; "Russia's final hour, it seemed, approached with inexorable certainty"; "relentless persecution"; "the stern demands of parenthood"
# S: (adj) ghastly, grim, grisly, gruesome, macabre, sick (shockingly repellent; inspiring horror) "ghastly wounds"; "the grim aftermath of the bombing"; "the grim task of burying the victims"; "a grisly murder"; "gruesome evidence of human sacrifice"; "macabre tales of war and plague in the Middle ages"; "macabre tortures conceived by madmen"
# S: (adj) black, grim, mordant (harshly ironic or sinister) "black humor"; "a grim joke"; "grim laughter"; "fun ranging from slapstick clowning ... to savage mordant wit"
# S: (adj) dour, forbidding, grim (harshly uninviting or formidable in manner or appearance) "a dour, self-sacrificing life"; "a forbidding scowl"; "a grim man loving duty more than humanity"; "undoubtedly the grimmest part of him was his iron claw"- J.M.Barrie
# S: (adj) gloomy, grim, blue, depressed, dispirited, down, downcast, downhearted, down in the mouth, low, low-spirited (filled with melancholy and despondency ) "gloomy at the thought of what he had to face"; "gloomy predictions"; "a gloomy silence"; "took a grim view of the economy"; "the darkening mood"; "lonely and blue in a strange city"; "depressed by the loss of his job"; "a dispirited and resigned expression on her face"; "downcast after his defeat"; "feeling discouraged and downhearted"
# S: (adj) blue, dark, dingy, disconsolate, dismal, gloomy, grim, sorry, drab, drear, dreary (causing dejection) "a blue day"; "the dark days of the war"; "a week of rainy depressing weather"; "a disconsolate winter landscape"; "the first dismal dispiriting days of November"; "a dark gloomy day"; "grim rainy weather"