The act of introducing something again, especially the release of animals from captivity into the wild(noun)
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Use "reintroduction" in a sentence
"Your implication that the population of wolves would rapidly expand after reintroduction is entirely correct."
"PS: I agree with Jim, and many others, that the wolf reintroduction is not working now."
"A similar scheme for its reintroduction is under way on Scotland’s Eastern Coast according to this report (here) from The Scotsman and appears to be going well."