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cretinize

American  
[kreet-n-ahyz, kret-] / ˈkrit nˌaɪz, ˈkrɛt- /
especially British, cretinise

verb (used with or without object)

cretinized, cretinizing
  1. to make or become cretinous; cause (a person) to be incapable of normal intelligence or sound judgment.


Etymology

Origin of cretinize

First recorded in 1855–60; cretin + -ize