The term "for nothing" can be replaced by several synonyms depending on the context. It can be substituted with the phrase "free of charge," which refers to something that doesn't require payment or cost. Another synonym is "without result," which indicates that something didn't produce the desired outcome. "In vain" is also a synonym that indicates a lack of success or achievement. Similarly, "fruitlessly" suggests that something was done without producing any useful results or outcomes. "Worthlessly" can also be used to describe something that has no value or usefulness. "Uselessly" is another synonym that conveys the same meaning as "for nothing." Overall, these synonyms provide alternatives for the phrase "for nothing," each with its specific meaning and connotation.