contrast - noun

the opposition or dissimilarity of things that are compared

the act of distinguishing by comparing differences

a conceptual separation or distinction

the perceptual effect of the juxtaposition of very different colors

the range of optical density and tone on a photographic negative or print (or the extent to which adjacent areas on a television screen differ in brightness)

contrast - verb

• put in opposition to show or emphasize differences
• to show differences when compared; be different

contrast - thesaurus

counterpoint   demarcation   line