What do rappers mean by “Underground”?
The slang term “Underground” is an adjective which is used in rap/hip-hop music to represent something that isn't mainstream or super popular by the masses.
Underground means to unknown or not as popular.
When something is underground it is the opposite of mainstream or commercial.
The term “Underground” has been used by Eminem, 2Pac, Drake, 50 Cent, Kanye West, Tyler the Creator, Baby Keem, Logic, Big Sean, The Game, and many more rappers.
Read: What does “Spit” and “Spitting” mean?
Read: What does a “Cypher” mean in rap?
Read: What does “No. 1” or “Number one” mean?
Read: What does “Mainstream” mean?