burro
/ˈburo/ · B1 · adj
stupid, foolish
🫏 English borrowed it whole: a burro is a pack donkey; a burrito is a little one
From Late Latin burricus, small horse. Spanish uses the donkey as the stock image of stubbornness and dimness, so calling someone burro means stupid or thick-headed. No seas burro = don't be an idiot.