THESAURUS
darkening
blackening, blocking the light, burial, burying, clouding, concealedness, concealment, covering, covering up, covertness, deception, denigration, dimming, eclipsing, extinguishment, hiddenness, hiding, interment, invisibility, masking, melanization, mystification, nigrification, obfuscation, obnubilation, obscuration, obscurement, obumbration, occultation, occulting, overcast, overclouding, overshading, overshadowing, overshadowment, putting away, screening, secrecy, secretion, shading, shadowing, smirch, smirching, smudge, smudging, smut, smutch, smutching, subterfuge, uncommunicativeness