Antonyms for "over-emotionalism" include detachment, coolness, composure, stoicism, and rationality. Detachment refers to a state of being objective, uninvolved, or dispassionate, while coolness suggests a calm, collected, or imperturbable manner. Composure denotes a sense of self-possession, control, or serenity, while stoicism implies a tolerance for pain, suffering, or adversity without complaint or emotion. Finally, rationality pertains to a logical, analytical, or reasonable approach to issues or problems, often eschewing emotionalism or sentimentality. In contrast to the excesses of over-emotionalism, these antonyms offer a balance of reason, pragmatism, or emotional reserve.