The act of opening an academic disputation; the proposition of objections to a tenet, as an exercise for a degree.(noun)
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Use "opponency" in a sentence
"L (1992) The color hexagon: a chromaticity diagram based on photoreceptor excitations as a generalized representation of colour opponency."
"Researchers have long regarded color opponency to be hardwired in the brain, completely forbidding perception of reddish green or yellowish blue."
"Under special circumstances, though, people can see the "forbidden" colors, suggesting that color opponency in the brain has a softwired stage that can be disabled."