The phrase "more jillion" is often used to describe an incredibly large number, and there are many synonyms that can be used in its place. For example, one might use the term "countless" to describe a number so large that it cannot be accurately calculated. Alternatively, the terms "myriad," "uncountable," or "innumerable" can be used to convey a similar meaning. Other possible synonyms include "countless," "untold," and "incalculable." Ultimately, the choice of synonym will depend on the context and tone of the writing, as well as the writer's personal style and preference.