"Acted upon" refers to the concept of taking action in response to something. There are several synonyms that can be used to portray this meaning effectively. Some of the synonyms for "acted upon" include reacted, responded, answered, and engaged. These words all convey the sense of action following a stimulus. Other synonyms can include palliated, moderated, mitigated, or counteracted, all of which indicate some form of response or reaction to a situation. Regardless of the word choice, it is important to accurately convey the intended meaning to ensure effective communication with the reader.