Locked and loaded

"Locked and loaded" means fully prepared and ready for action, originally referring to a firearm ready to fire.
Literal Meaning
The phrase originates from firearms terminology, where a gun is considered "locked and loaded" when a round is in the chamber and the safety is disengaged, making it ready to fire. Historically, this term dates back to at least the 18th century, with references to muskets being "well locked and loaded" in 1793. The imperative form, "lock and load," was used in the U.S. Army Field Manual for the M1 Rifle around 1940.
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Figurative Meaning
Figuratively, "locked and loaded" conveys readiness, focus, and determination for any task or challenge, not just combat. For example, someone might say, "The team was locked and loaded for the big project," meaning they are fully prepared and eager to begin. It can also imply enthusiasm and intensity in approaching a situation.
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Usage in Popular Culture
The phrase gained popularity in movies and media, notably through actors like John Wayne, and is often used in informal conversations to express preparedness. Synonyms include "ready to go," "all set," "geared up," and "primed".
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Summary
Literal: Firearm is ready to fire.
Figurative: Person or group is fully prepared and focused for action.
Origin: Military and firearm terminology, dating back to the 18th century, popularized in the 20th century.