A "human dynamo" is a phrase often used to describe someone who has boundless energy and works tirelessly. Other synonyms for the term include "powerhouse," "ball of fire," "live wire," "go-getter," "whirlwind," "workhorse," and "energizer bunny." These terms describe people who are constantly active, enthusiastic, and able to take on multiple tasks with ease. They are focused, driven, and can accomplish a lot in a short amount of time. It is not uncommon for these individuals to be well-respected, admired, and even envied by others due to their impressive work ethic and output.