ON VALENTINE’S DAY 1981 Deborah Harry was the headlining musical guest on “Saturday Night Live.” A product of the fertile downtown Manhattan musical scene, centered around the CBGB club on the Bowery, she had gone pop with a series of hit singles, including Blondie’s “Rapture,” which reached No. 1 in 1981. The track, a tribute to an uptown musical culture that most Americans viewed as a curiosity or fad (if they had any awareness of it at all), name-checked a few seminal New York figures, including Grandmaster Flash, the pioneering D.J. whose group the Furious Five formed in 1976 and broke musical ground at house parties in the South Bronx before cracking into the Top 100 in 1982 with the socially conscious rap anthem “The Message,” and Fab 5 Freddy, a Brooklyn-based graffiti artist who acted as a liaison between street artists, the commercial art world and downtown clubs. At the urging of Blondie’s Harry and the band’s guitarist Chris Stein, “S.N.L.” booked the Bronx’s Funky 4 + 1 (four male rappers and pioneering female M.C. Sha-Rock) to perform their single “That’s the Joint” for the show’s final number of the night. Harry’s rapped verse on “Rapture” was, for most people, a proxy introduction to hip-hop, but it was the Funky 4 + 1 that gave network television viewers the first true taste of what young New Yorkers had been experiencing in parks, subways and schoolyards for several years already.

This culture, just starting to be described under the umbrella phrase “hip-hop,” would emerge from its Bronx and Harlem origins during 1981 to ’83, engaging in a dialogue with the city’s other musical cultures that would extend its influence. The Funky 4 + 1’s 1980 “That’s the Joint” is a great example of how hip-hop’s particular vernacular helped propel the culture forward. The idea that something was “the joint,” meaning something was exciting or pleasing, had been street slang for several summers before this 12-inch single was released. (Spike Lee still labels his films “a Spike Lee Joint” reflecting his growing up in Brooklyn in the ’70s.) “That’s the Joint” is significant in another aspect: It took a New York street slang word and introduced it to the wider world, something that became a signature of rap records. Superlatives like “fresh,” “stoopid,” “def” and the ever enduring “dope” moved from the streets to recordings to advertising to daily usage. Hip-hop records like “That’s the Joint” literally remixed the way people talk.