While rap fans might assume the phrase "Redrum" merely refers to the title of 21 Savage's latest song from his American Dream album, the term actually dates back to the 1970s as a book and 1980s as a result of a classic horror film.

Where Did "Redrum" Originate From?

21 Savage's lead single off his American Dream LP currently sits comfortably at No. 13 on the Billboard Hot 100. The song peaked at No. 5 in January and has fluctuated around the top 10 ever since. While "Redrum" is being uttered by rap fans everywhere, the turn of phrase 21 uses, which is "murder" spelled backward, actually stems from Stephen King's 1977 horror novel The Shining as well as its equally renowned film adaptation in 1980 starring Jack Nicholson and Shelley Duvall.

The term is muttered over and over again by the 5-year-old character Danny Torrance, who has psychic abilities and becomes possessed by an evil spirit, which tells him to kill his mother. During the peak of his possession, Danny grabs a butcher knife while his mother sleeps nearby, and writes "redrum" in his mom's lipstick on the door while mumbling the phrase to himself. When Danny's mom awakes, she looks into her bedroom mirror and realizes "redrum" means "murder."

The Shining clip
Movie Clips/YouTube

Read More: 21 Savage Performs "Redrum" and "Should've Worn a Bonnet" On SNL

Is 21 Savage the First Rapper to Make a Rap Song About "Redrum?"

21 is also not the first rapper to make a song using the word "redrum." In 2009, 50 Cent released "Redrum (Murder)." A decade later, Skepta put out the song "Redrum" featuring Key!. Big Boogie dropped a Gangsta Grillz mixtape with DJ Drama last February called Redrum Wizard. There have been more rappers before and after who've taken the term and created music around it, too.

It's hard to deny that 21 Savage's rendition of the phrase isn't the most popular. "Redrum" serves as the Atlanta rapper's highest-charting solo song to date. Savage in turn clinched his fourth No. 1 album on the Billboard 200 with American Dream.

Despite its history, the term now belongs to 21 Savage.

Read More: 21 Savage Says He'd Beat the Entire 2016 Freshman Class in a Verzuz Battle

Watch 21 Savage's music video for "Redrum" below

Watch 21 Savage's Music Video for "Redrum"

See 21 Facts About 21 Savage Living the American Dream