Correction: An earlier version of this obituary incorrectly reported Mr. Yauch’s date of death. He died May 4, not April 6. Also, the earlier version incorrectly referred to the Rock and Roll Hall of Fame as the Rock Hall of Fame and innacurately stated that the group Run-DMC recorded with Def Jam Recordings.

Adam Yauch, the raspy-throated rapper known as MCA whose rhyming skills helped make the Beastie Boys one of the most influential hip-hop groups, died May 4 in New York. He was 47.

The death was confirmed by Billboard magazine, which reported that salivary cancer had been diagnosed in 2009. Because of health problems, Mr. Yauch was unable to attend the Beastie Boys’ induction into the Rock and Roll Hall of Fame in April.

Bursting onto the black-dominated hip-hop scene in the 1980s, the Beastie Boys were at first considered rap gimmickry: three white, beer-chugging hellions with little rhyming talent.

Today, the Grammy Award-winning, Brooklyn-based trio is regarded as hip-hop royalty and known as one of the most innovative acts in modern music history.

Mr. Yauch’s lyrics could be zany, socially conscious and surprisingly intellectual — with references to politics, the environment and the astrophysicist Carl Sagan.

In an interview, Dan Charnas, author of “The Big Payback: The History of the Business of Hip-Hop,” called Mr. Yauch “in-your-face, loud, and electric.”

“If you could compare the Beastie Boys to an atom,” Charnas said. “Mike D was the neutron, the straight man. Ad-Rock was the electron, the way, way out into outer space one. MCA — he was the proton, complete energy, the guy with the most forceful voice.”

The Beastie Boys first formed in the early 1980s as a hard core punk band but then dropped their instruments and began rapping. While searching for a DJ to play for them, the group met a New York University student named Rick Rubin.

Rubin and his partner, Russell Simmons, signed the Beastie Boys to their new hip-hop label, Def Jam Recordings, in the mid-1980s. Joining Def Jam, the home of established rapper LL Cool J, provided the young group with instant clout in the hip-hop industry.

In 1986, the group released its first studio album, “Licensed to Ill.” Propelled by the mega-hit “Fight for Your Right (to Party!)” — an alcohol-soaked anthem to teenage angst — “Licensed to Ill” sold 4 million copies and became the first rap album to reach No. 1 on the Billboard pop charts. (In the “Fight for Your Right” video, Mr. Yauch spews foamy beer into the face of a turtlenecked nerd.)

Of the group’s three bad boys — Mr. Yauch, Adam “Ad-Rock” Horovitz and Michael “Mike D” Diamond — Mr. Yauch was viewed as the baddest. His sexually explicit and violence-laced lyrics were often the most lewd, rude and crude.

In the song “The New Style,” he rapped: “I’ve got money and juice — twin sisters in my bed / Their father had envy so I shot him in the head.”

The Beastie Boys had a falling out with Def Jam in the late 1980s and moved to Los Angeles, where they signed with Capitol Records. Their second album, “Paul’s Boutique,” produced by the Grammy-winning team the Dust Brothers, was recognized by music critics for its innovative use of sampling and layered lyrical references.

In the early 1990s, the Beastie Boys began to mature musically and personally. The group released two critically acclaimed albums in a row: “Ill Communication” (1994), which featured the rock-heavy single “Sabotage,” and “Hello Nasty” (1998), which featured the top singles “Body Movin’ ” and “Intergalactic.”

On “Ill Communication,” Mr. Yauch used the opening song, “Sure Shot,” to apologize for degrading women in the past.

“I want to say a little something that’s long overdue / the disrespect to women has got to be through / to all the mothers and the sisters and the wives and friends / I want to offer my love and respect to the end.”

Adam Nathaniel Yauch was born Aug. 5, 1964, in Brooklyn. His father was a Catholic architect and his mother a Jewish social worker, and he was raised in a secular home.

Besides his parents, survivors include his wife, Dechen Wangdu, who is Tibetan American, and their daughter.

In recent years, Mr. Yauch worked as a film director under the name Nathaniel Hornblower. In 2006, he released a basketball documentary, “Gunnin’ for that #1 Spot,” which centered on a prestigious Harlem playground pick-up game.

On a trip to Asia in the early 1990s, Mr. Yauch met Tibetan refugees while hiking the Himalayas and was inspired to pursue Buddhism.

During the 1990s and 2000s, he organized the Tibetan Freedom Concert, a series of music festivals, most of them lasting two days, that promoted pacifism and Tibetan independence. One was at RFK Stadium in 1998. Proceeds benefited Mr. Yauch’s charity, the Milarepa Fund, named for a Tibetan saint who sought enlightenment by composing music.

Having found Buddhism, Mr. Yauch said he regretted his earlier destructive ways.

“I didn’t realize how much harm I was doing back then,” Mr. Yauch said in 1998. “I had kids coming up to me and saying, ‘Yo, I listen to your record while I’m smoking dust, man.’ And I’d say, ‘Hey, man, we’re just kidding. I don’t smoke dust.’ People need to be more aware of how they’re affecting people.”