ambiguous, amorphous, amphibological, besmirched, black, blackened, bleak, blind, blotchy, caliginous, clear as mud, clouded, cloudy, dark-colored, dark, darkened, darkish, darksome, dim, dimmish, dimpsy, dingy, dirty, discolored, dismal, double-edged, double-faced, drab, dreary, dun, dusk, dusky, equivocal, filthy, foggy, foul, foxed, foxy, fuliginous, funereal, fuzzy, glooming, gloomy, glowering, grey, grim, grimy, grubby, hazy, indeterminate, indistinct, inky, lowering, misty, mucky, muddy, murk, murksome, nasty, nebulous, nubilous, obscure, opaque, overcast, roily, semidark, shadowy, shady, shapeless, sibylline, smirched, smoky, smudgy, smutty, soiled, somber, sooty, sordid, squalid, stained, stigmatic, stigmatiferous, stigmatized, subfusc, tainted, tarnished, tenebrous, threatening, transcendent, turbid, unclean, unclear, unplain, vague