Often slang can come from the cinema.
The term to "catfish" someone, which means to pretend to be someone else on the Internet, comes from the 2010 documentary/thriller "Catfish."
To call a cop, a "dirty harry," which is a cop that's not afraid to play by his own rules, comes from the 1971 Clint Eastwood film.
Recently, political reporters have often used the term "gaslighting" to refer to someone manipulating someone into thinking they're crazy. Only through a search through Amazon for movies to rent did I discover that this actually comes from the 1944 film "Gas Light" starring Ingrid Bergman (of "Casablanca" fame) in her first Oscar-winning role (she'd later win two more).
The 1944 movie, which was also nominated for Best Picture, Best Adapted Screenplay and Best Supporting Actress (Angela Lansbury), was based on a 1938 play by Patrick Hamilton and previously was made into a much darker (although less technically proficient) British film adaptation by Thorold Dickinson.
In the latter version, Bergman plays a newlywed who is moving to London with her husband into a home she grew up in. In this house, she witnessed her aunt, a famous singer, being murdered but she's blocked most of that from her memory. The plot progresses slowly but systematically her husband begins to plant things to make her question her sanity. He hands her a broach and tells her not to lose it because she's prone to losing things. "Am I?" she responds. Later, when it goes missing from her purse she said she doesn't remember taking it out, but her husband chastises her for forgetting what happened. Later, she hears sounds in her mansion and the gas light in a room dimming, leading her to believe that someone turned up the gas in another room of the house (the movie/play is set in 1880 and gas was still used to heat and light homes back then).
Eventually, clues start to add up and a persistent detective -- who has a past connection to the murdered aunt -- tells Bergman his theory about what happened. She realizes that she's not crazy. Her husband has been lying to her and wants to send her to an insane asylum so he can have the home to himself and search for her aunt's hidden treasures.
George Cukor, who also directed "Born Yesterday," "Adam's Rib," "The Philadelphia Story," "My Fair Lady" and the 1954 version of "A Star is Born" does a great job with the tone and pace. Cukor famously was the original director on "Gone With the Wind" before Victor Fleming took over and won an Oscar. (Fleming actually left filming of "The Wizard of Oz" to take over directing duties on "Gone With the Wind." Both movies were nominated for Best Picture that year and "Gone With the Wind" won.)
When did the term "gaslight" become a thing? One article says that columnist Maureen Dowd may have been the first to coin the term in a 1995 article about Bill Clinton and Newt Gingrich. She wrote, “You can’t Gaslight someone who is already a little lit.”
Now the term is used quite frequently. One journalist called Donald Trump the "gaslighter in chief." The recent remake of "The Invisible Man" starring Elisabeth Moss was referred to as a version that focused on "gaslighting" in modern American with a sci-fi twist.
The 1944 version of “Gaslight” can be streamed via Amazon Prime, Vudu and YouTube; the 1940 version is available from Amazon Prime, iTunes, and Vudu.
[embed]https://www.youtube.com/watch?v=0ToLfQU2xmg[/embed]