Simply put, “drill” is slang that means to fight or retaliate back, especially in a violent way. It is commonly used in urban settings and streets. The usage of “drill” in rap is somewhat similar.
When using “drill” in rap, you might be referring to drill rap. Similar to trap rap or trap music that deals with drugs in their songs, Drill rap focuses on the violent side of things. “Drill” rap is often brutal, violent, and aggressive, primarily about guns and shootings. It originates from the southern area of Chicago around the 2010s. It may be used like this:
“I ain’t no softie so play me some drill!”
“I know drill rap may be horrifying but it is real!”