1. An exclamation of confirmation of success.
2. "Mission accomplished."
Popularized by the assassination of Osama bin Laden by the Navy SEAL Team Six, otherwise known as "Operation Geronimo." When Osama bin Laden had been successfully assassinated, the code-word "geronimo" was given to President Barack Obama, who was monitoring the operation in real-time in Washington D.C., to confirm mission success.
White guy: "Did you have intercourse with that pulchritudinous
female last night?"
Black guy: "Yea nigga
, tapped that shit. Geronimo."
Navy SEAL Team Five: "How'd it go?"
Navy SEAL Team Six: "Geronimo."