The antonyms for the phrase "dieing off" would be "thriving", "flourishing", or "prospering". These words denote growth, progress, and vitality, in contrast to decline and extinction. When a species or a community is thriving, it means that they are healthy and are increasing in number, and their ecosystem is also in good health. Furthermore, when people or societies are thriving, they are progressing and advancing, economically, socially, or culturally. Therefore, it is crucial to strive for the antonyms of "dieing off" to ensure the preservation and sustainability of our planet and its inhabitants.