The word un-impassioned refers to lacking passion or emotions. Its antonyms could be passionate, enthusiastic, fervent, animated, lively, zealous, ardent, or fiery. These words imply strong emotions and intense feelings. A passionate person is fully invested in their beliefs or emotions, while an un-impassioned person feels a sense of detachment. Enthusiasm implies a certain amount of energy and eagerness, while fervent suggests a deep-seated intensity of emotion. Animated evokes a sense of liveliness and energy, while lively suggests a buoyant or vibrant personality. Zealous suggests a strong devotion or dedication, while ardent and fiery suggest an intense passion or fervor.