But after the midterms, Trump seemed to tire of the adjective, until he broke it out again this week on Twitter. The on-again, off-again pattern resembles his infatuation with another Spanish borrowing: hombres. Trump famously warned of “some bad hombres” coming across the Mexican border in a debate with Hillary Clinton in 2016, and he continued inveighing against “hombres” who were variously “bad” or “tough” or “rough” as part of his alarmist campaign rhetoric on border security. But the word did not join his Twitter repertoire until last month, when he tweeted, “The bad ‘hombres,’ of which there are many, are being detained & will be sent home.” By putting hombres in quotation marks, he was perhaps signaling its foreignness, while at the same time self-consciously quoting his own memorable usage from the debate three years ago. (In Thursday’s loco tweet, the word was both bracketed by quotation marks and capitalized, a one-two punch of Trumpian emphasis.)

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Trump’s use of hombres and loco illustrates what the late linguistic anthropologist Jane Hill termed “Mock Spanish,” an anglophone appropriation of Spanish words that, she argued, can serve as “a site for the indexical reproduction of racism in American English.” In her 2008 book, The Everyday Language of White Racism, Hill presented “tough hombre” as an example of “Cowboy Anglo Spanish” that persisted from early frontier usage thanks to reinforcement in Western movies—no doubt how Trump was exposed to the word hombres.

When Trump referred to “bad hombres” in the 2016 debate, Adam Schwartz, a specialist in Spanish-language education at Oregon State University, wrote that “Donald Trump just made it a hell of a lot easier for me—and for all of us who teach about language, race and racism—to talk with students about Mock Spanish and the power of covert racist discourse.” Schwartz observed that while “hombre itself might not be a racial slur,” Trump’s use of it crystalized “the scope of that word’s injury, its offensiveness, its oppressive potential.”

As for loco, it too represents a remnant of English-Spanish linguistic contact along the western and southwestern frontier. According to Cowboy Talk: A Dictionary of Spanish Terms From the American West by Robert M. Smead, the word goes back to 1844 in American English, used in conjunction with locoweed, a poisonous plant that caused a distemper in cattle called loco or locoism. Like hombre, it was kept alive in the limited lexicon of anglicized Spanish found in cowboy movies.

Jane Hill noted in her book that loco has exemplified one pattern of Mock Spanish, the euphemistic substitution of “vulgar” English words with “insulting, lewd, or scatological” Spanish equivalents. She observed that it could be used for political name-calling in conjunction with other typical Mock Spanish elements, such as the article el and the suffix -o, as when Rush Limbaugh called the former Democratic congressional leader Dick Gephardt “El loco poco Dicko.”