The word “supine” comes from the Latin word “supinus,” meaning “bent backward.” As an adjective describing position, it applies to a person lying with their face up, a hand with the palm upward, or any object with the front part upward. Another usage of the word “supine” concerns taking action. You might have heard the phrase “I’m not going to take this lying down” to refer to standing up to some kind of injustice. If you don’t take action, then you can be accused of being supine, which describes failing to act or figuratively lying down.