the state or quality of being dark

The room was in total darkness.

absence or deficiency of light

the darkness of night.

wickedness or evil

Satan, the prince of darkness.

obscurity; concealment

The darkness of the metaphor destroyed its effectiveness.

lack of knowledge or enlightenment

heathen darkness.

lack of sight; blindness.

noun

brightness , day , daylight , daytime , illumination , light , lightness , morning , cognizance , enlightening , intelligence , sense , sensibility , understanding

noun

black , blackness , blackout , brownout , calignosity , cimmerian shade , cloudiness , crepuscule , dark , dimness , dusk , duskiness , eclipse , gloom , lightlessness , murk , murkiness , nightfall , obscurity , pitch darkness , shade , shadiness , shadows , smokiness , tenebrosity , twilight , blindness , concealment , denseness , inscrutability , isolation , privacy , seclusion , secrecy , unawareness , obscureness , infuscation , night , obfuscation , shadow , unenlightenment , wickedness