What is the meaning of contrast?

noun

• The opposition or dissimilarity of things that are compared.
  • usage: "in contrast to, "by contrast"
  • synonyms: direct contrast
• The act of distinguishing by comparing differences.
• A conceptual separation or distinction.
  • usage: "there is a narrow line between sanity and insanity"
  • synonyms: line, dividing line, demarcation
• 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. )

verb

• Put in opposition to show or emphasize differences.
  • usage: "The middle school teacher contrasted her best student's work with that of her weakest student"
• To show differences when compared; be different.
  • usage: "the students contrast considerably in their artistic abilities"
  • synonyms: counterpoint