When searching for synonyms for the word "riffed," there are several options available to convey similar meanings. The word "improvised" is one such synonym, which refers to creating something spontaneously. Another option is "ad-libbed," which means making up something on the spot without prior preparation. "Jamming" is also a synonym for riffed, particularly in a musical context, which refers to playing music spontaneously with a group of musicians. Finally, "spontaneous" and "unplanned" are options that can be used in a broader sense to describe any action or event that is not premeditated or organized. By using these synonyms, a writer can convey a more precise meaning to their readers.