Antonyms for "decline" include "improve," "increase," "ascend," "rise," and "grow." These words are the opposite of decline, which means to decrease, diminish, or reduce. When something is improving, it is getting better, not worse. When something is increasing, it is getting larger or more significant. When something ascends or rises, it is moving up, not down. And when something grows, it is getting bigger, not smaller. These antonyms can be useful when you want to describe the opposite of a decline. For example, if you want to talk about an improving economy, you would use the antonym "improve" instead of "decline.