Recalcitrant is an adjective that means stubbornly resistant.
Although our word of the day is typically used to describe people who are hard to manage and uncooperative, its origin has nothing to do with people at all. The Latin word recalcitrare (ray call see TRAR ay) means ‘to kick back.’ It was used to describe stubborn, difficult to handle mules.
By the mid-19th century, the word — now evolved into the English recalcitrant — came to be used to describe stubborn and hard to manage humans.
Annie is one of my more recalcitrant piano students. She insists on playing scales her own way no matter how many times I scold her.