Here’s the new definition that they came up with. Temperature measures the willingness of an object to give up energy. Actually, I lied. This isn’t how they really define temperature, because physicists speak math, not english. They define it as  which says, in words, that the temperature is inversely proportional to the slope of the entropy vs. energy curve.

via What the Dalai Lama can teach us about temperatures below absolute zero | Empirical Zeal.