A remarkable act carried out purportedly by magical means but actually by trickery or illusion, generally as a form of entertainment.(noun)
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Use "magic trick" in a sentence
"A compound bow is always strung, and has pulley-cams that perform the seemingly magic trick of allowing you to hold the string with only, say, twenty pounds of pull-but when you release it, it assumes the force of fifty five pounds of pull, and propels the arrow viciously forward."