The phrase "is on one's back" typically refers to a person who is facing a challenging situation or burden. Some possible antonyms for this phrase could include "free from" or "unburdened," indicating a sense of relief or release from the difficulty. Alternatively, the phrase "on top of the world" could be seen as an antonym, suggesting a feeling of confidence, success, or control. Other possible antonyms might depend on the specific context or nature of the challenge, such as "resolved," "eased," or "overcome." Ultimately, the most effective antonyms for "is on one's back" will depend on the situation and the desired outcome.
