1. The absolute certainty of a future (often material) acquisition.
2. To have specific knowledge.
3. (In combat parlance) To acquire a target to be fired upon.
1. "Man, I got a lock on some killercryppie for tonight."
2. "Yo, Bobby's got a lock on a kickin’ party 'round the corner; Let's roll!"
3. "I've got a six strobe. I think he's locked on us." –Goose in the motion picture "Top Gun" when an enemy fighter-jet’s missile targeting system zeros in for a kill shot.