calenture

In addition to being plagued by scurvy and homesickness, sailors of yore who dared the tropics also had calenture to worry about. Given a case of this fever they were likely to imagine that the sea was actually a green field and to leap into it. Our earliest evidence of the word in English is from the late 16th century. Such potent imagery destined the word for figurative use also. "Calenture" has its origins in a Spanish word of the same meaning, "calentura," which itself traces to Latin calēre, meaning "to be warm." Other words from "calēre" include "calorie," "cauldron," and "scald."