blackness
Word family
Synonym discussion
Sense: noun/1
For sense 1, blackness is useful when you want to stress either a fully black colour or darkness that feels thick and complete. Darkness is the broad everyday word and fits most situations where there is little or no light. Gloom usually suggests weak, dull light rather than total absence of it, and it can also suggest a sad mood. Shadow is more specific: it is a dark shape or area made when light is blocked. A cave may be full of blackness or darkness, but a tree throws a shadow. Wet paint can have a deep blackness, but we would not usually call that shadow.
Etymology
Blackness was formed in English by adding the noun ending -ness to black. The older word black comes from Old English and has long referred to the darkest colour. The noun first named that colour or the absence of light, and it later came to be used for Black identity and experience as well.