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pavo real m. (Noun) "peacock"
18th cent. When Spanish colonists first settled the New World, they used an existing word pavo meaning "peacock" to describe turkeys. Over time, the meaning of the word shifted towards "turkey" until pavo was no longer recognized as the proper word for peacocks. Instead, speakers said pavo real for the brightly colored bird, in the sense of saying an 'actual peacock.'