The phrase "Sweet Fanny Adams" is a British slang term used to express nothing or something insignificant. There are several synonyms that can be used in place of this phrase, such as "zilch," "nada," "nothing," "zip," and "nil." These words are commonly used to indicate that something is lacking or missing entirely. Other synonyms for "Sweet Fanny Adams" can include "worthless," "trivial," "meaningless," or "insignificant," all of which imply that something has little or no value. Whether it's a small issue or a major problem, these synonyms can be used to express the idea of "Sweet Fanny Adams".