General Slang:
* Ace: Excellent, great, first-rate.
* Bop: To dance, especially to swing music.
* Buzz: To gossip, spread rumors.
* Chisel: To cheat or swindle.
* Dig: To understand, appreciate, or like something.
* Drag: A boring or unpleasant experience.
* Flip: To become angry or upset.
* Glimmer: To shine or sparkle.
* Gobsmacked: Shocked, astonished.
* Hot: Stylish, attractive, popular.
* Jam: A difficult situation.
* Keen: Interested, enthusiastic.
* Kicks: Enjoyment, pleasure.
* Loop the loop: To be confused or disoriented.
* Miffed: Offended, upset.
* Mug: A face, usually in a comical or unattractive way.
* Nuts: Crazy, foolish.
* Razz: To tease or make fun of.
* Scram: To leave, go away.
* Swell: Great, excellent.
* Tiff: A minor argument.
* Whippersnapper: A young, inexperienced person.
* Whiz-bang: Excellent, outstanding.
Music-Related Slang:
* Beatnik: A person who adopts the unconventional lifestyle and attitudes of the Beat Generation, known for their love of jazz music.
* Jive: To dance, often to swing music.
* Swing: A style of music popular in the 1940s, characterized by a fast tempo and improvisational elements.
* Jump jive: A fast and energetic style of dance.
* Hot jazz: A style of jazz music known for its improvisational nature and energetic rhythm.
War-Related Slang:
* G.I.: A slang term for a soldier, derived from "Government Issue."
* K.P.: Kitchen Police, a duty assigned to soldiers responsible for cleaning and cooking.
* M.P.: Military Police, responsible for maintaining order and discipline within the armed forces.
* Dogface: A slang term for a soldier, often used in a derogatory way.
* Doughboy: A slang term for an American soldier, particularly during World War I.
Other:
* Big cheese: A person of importance or authority.
* Bread: Money.
* Booze: Alcoholic drinks.
* Cat's pajamas: Excellent, wonderful.
* Ducky: A slang term for a person, often used in a playful way.
* Flabbergasted: Shocked, astonished.
* Goofy: Silly, foolish.
* Jeepers: An expression of surprise or excitement.
* Nifty: Clever, stylish.
* Sharp: Stylish, attractive.
* Stooge: A foolish or silly person.
* The cat's meow: The best, the most excellent.
* Tweedle-dee: A silly or unimportant person.
* Zoot suit: A flamboyant and stylish suit popular among young men in the 1940s.
This is just a small selection of the many slang words used in the 1940s. The specific words used would have varied depending on the region, social group, and individual's own preferences.