Originally a keynote address at the International Society for Research on Emotion (ISRE) 2013 convention, this article surveys many nonobvious ways that emotion phenomena show up in natural language. One conclusion is that no classical Aristotelian definition of "emotion" in terms of necessary and sufficient conditions is possible. The brain naturally creates radial, not classical categories. As a result, "emotion" is a contested concept. There is no one correct, classical definition of "emotion." There are real emotion phenomena that can be precisely studied, and language is an important area to look at for such phenomena.