a place or condition of prosperity, comfort, success, etc.
Fat City in American English
noun
slang
an easy and prosperous condition or circumstance
With a new house and a better-paying job, she's in Fat City
Also: fat city
Word origin
[1960–65]This word is first recorded in the period 1960–65. Other words that entered Englishat around the same time include: buyback, deinstitutionalize, power play, tag question, zip code