Da "brilliant" realization dat you arrive at in your mind after seeing dat da object in question looks, walks, and quacks exactly like da familiar water-fowl, and so da only obvious/rational conclusion is dat said extra-oily-feathered creature is indeed what it appears to be.
It really drives me up da wall how so many government bureaucrats take a month of Mondays to make even a simple deducktion, and then they finally say, "Well, whadduh ya know --- I guess it actually IS true dat ___! Amazing!"
by QuacksO January 18, 2020
Get the deducktionmug.