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
causing distress or worry or anxiety; "distressing (or disturbing) news"; "lived in heroic if something distressful isolation"; "a disturbing amount of crime"; "a revelation that was most perturbing"; "a new and troubling thought"; "in a particularly worrisome predicament"; "a worrying situation"; "a worrying time"