Proper Noun: A combination of Memphis (Tennessee, USA) and Africa (the well-known continent). This pejorative term is a generalization and based upon the poorer (and often dangerous) African-American neighborhoods which form a subset of the city.
Steve-o: Hey, I heard you were going to Tunica to gamble this weekend. Are you gonna stay there?
Truant: Although the hotels in Tunica are run-down and expensive, it beats staying in Memfrica.