To make fatuous; to cause someone to become foolish or to act foolishly without good sense.
From Latin 'fatuus' (foolish, insipid) plus the verb-forming suffix '-ate', which creates verbs meaning 'to make' or 'to cause to become'.
This rare verb shows the Latin root 'fatuus' (foolish) can be verbified—just like Latin 'stupidus' became 'stupefy', connecting entire families of related English words through this one ancient root.
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