Corroboratively is an adverb used to describe an action that supports or confirms an existing statement or belief. There are many synonyms for corroboratively that you can use in your writing to add variety and depth to your texts. Some synonyms for corroboratively include affirmatively, approvingly, substantively, confirmingly, positively, and reassuringly. These words all convey the same meaning as corroboratively and can be useful in different contexts. For example, if you are writing a legal document, you might use the word "substantively" to indicate evidence that supports your argument. Similarly, if you are writing a news article, you might use "positively" to describe an action that confirms a previously reported event.