"I am two fools, I know, / For loving, and for saying so / In whining Poetry," wrote John Donne, simultaneously confessing to both infatuation and fatuousness. As any love-struck fool can attest, infatuation can make buffoons of the best of us. So it should come as no surprise that the words fatuous and infatuation derive from the same Latin root, fatuus, which means "foolish." Both terms have been part of English since the 17th century. Infatuation followed the earlier verb infatuate, a fatuus descendant that once meant "to make foolish" but that now usually means "to inspire with a foolish love or admiration."

What is the origin of infatuated?

When we speak of someone being infatuated it very often is in relationship to that person having seemingly taken leave of his or her senses, especially in a romantic context (“he was so infatuated that he could not remember what day of the week it was”). This is fitting, as the word shares an origin with the word fatuous, which means complacently or inanely foolish. Both words come from the Latin fatuus (“foolish”), although fatuous is not often used in the romantic contexts in which we find infatuate. When used with a preposition infatuated is typically followed by with.