The phrase "lucks out" means to have good fortune or success, often by chance. Its antonyms, or opposite meanings, include "strikes out," which means to fail or to be unsuccessful, and "has bad luck," which means to experience misfortune or difficulty. Other antonyms for "lucks out" might include phrases such as "misses the mark," "falls short," or "comes up empty." Essentially, any phrase that conveys an absence of good luck or positive outcomes could be considered an antonym for "lucks out.