Being common implies something that is ordinary or widespread. Synonyms for the phrase "being common" might include terms such as ubiquitous, universal, prevalent, or standard. These words suggest that something is not unique or exceptional, but rather something that is commonly found or observed. Other possible synonyms for "being common" could include phrases such as run-of-the-mill, average, or normal. These words all suggest that something is not particularly remarkable or outstanding, but rather is typical or unremarkable. While each of these synonyms may have slightly different connotations, they all convey a sense of something that is common or widely observed.