The word "downslide" refers to a decline or decrease in quality or value over a period of time. The antonyms for downslide include improvement, growth, progress, advancement, increase, and upswing. These words signify an upward trend or a positive change. When we talk about an upswing, it indicates a rise in prosperity, the state of being successful, or progress in something. Similarly, growth refers to an increase in size, number, or quality, while progress implies movement towards a desired goal. Therefore, using the antonyms of downslide, we can express positivity and optimism about the current situation or future prospects.