AF is an acronym that stands for "as f*ck". It is used colloquially to emphasize the degree or intensity of something. However, there are many different synonyms that one can use to express the same sentiment. Some common ones include "extremely", "exceptionally", "incredibly", "unbelievably", "insanely", "ridiculously", "awfully", "terribly", "frightfully" and "excessively". However, it is important to note that these words can have different connotations and should be used appropriately depending on the context. Ultimately, the goal is to find a word that accurately captures the level of intensity being conveyed without sounding too forced or inauthentic.