"Wert in Fat City" is an expression that means being in a prosperous situation or a state of financial comfort. There are several other words and phrases that people use as synonyms for this expression. For instance, someone can say that they are "in clover," which means they are living a life of ease or luxury. Another synonym for being in fat city is being "flush," which means they have access to an abundant supply of cash. Additionally, people can say that they are "rolling in dough" to indicate that they are making a lot of money. The expression "living the high life" or enjoying life to the fullest is also synonymous with being in Fat City.