"Shoo fly" is a phrase usually used to shoo away irritating insects like flies. However, there are a variety of words people use that mean the same thing. One common synonym is "shoo," which means to urge something to go away. Another word people use is "buzz off," which is a slang way to tell something to leave. Additionally, "scat" is another synonym for "shoo fly," which is generally used to make something go away quickly. Lastly, people also use "go away," "begone," "be off," and "get lost" as synonyms for "shoo fly." These expressions are used to express one's annoyance towards things that are unpleasant or irritating.