Conrad Janis, who had a multifaceted career as a jazz trombonist, an expert in modern art and a character actor best known for playing Pam Dawber’s protective, strait-laced father on the sitcom “Mork & Mindy,” died March 1 at a Los Angeles hospital. He was 94.

The death was confirmed by his business manager, Dean A. Avedon, who did not specify the cause.

Janis began his acting career in his early teens and appeared on Broadway, radio, film and hundreds of television shows, many of them live dramatic productions in the 1950s. Starting in 1978, he spent four seasons on “Mork & Mindy” as the protective father of Dawber’s Mindy.

The show, which introduced comic actor Robin Williams to a national audience, featured Williams as a space alien (Mork) transported to Earth. Mork is befriended by Mindy, and they eventually become romantically attached. Janis plays a musician who runs a music store. Despite his initial bewilderment about Mork, he has his daughter’s best interests at heart.

“Mork & Mindy” became an instant, unexpected hit. Mork’s greeting, “Nanu Nanu,” became a national catchphrase.

“We all felt the show would do well,” Janis told the St. Louis Post-Dispatch in 1988. “But, we had no idea. The week we hit the air, I was walking through a craft fair and everyone said, ‘Look, it’s Mindy’s father.’ That’s how quick the recognition came. That show was just four great years, a great experience.”

It was Janis’ most high-profile role, but with his bald head and elfin features, he was a familiar figure on television and movie screens through the years. He appeared in the 1992 Billy Crystal film “Mr. Saturday Night,” the 1996 Jim Carrey comedy “The Cable Guy,” directed by Ben Stiller, and on such TV shows as “Murder, She Wrote,” “St. Elsewhere” and “Frasier.”

Janis came to Hollywood as a teenager and acted in his first film, the wartime comedy “Snafu,” in 1945, playing an underage boy who joins the Marines and returns to his family as a 15-year-old with the experiences of an adult.

“Conrad Janis, in his screen debut,” a New York Times critic wrote, “gives a lively performance as the regretful returnee who is viewed with suspicion and alarm for his unsuccessful attempts to revert to ‘normalcy.'”

He appeared in the film alongside humorist Robert Benchley, whom he credited with teaching him a naturalistic style of acting.

During his early years in Hollywood, Janis spent many of his evenings in jazz clubs. He was particularly drawn to the traditional jazz, or Dixieland, of trombonist Kid Ory, who had performed with Louis Armstrong in New Orleans before 1920. Janis taught himself to play the trombone, learning Ory’s style, and by 1949 was a professional musician as well as an actor.

He moved back to his native New York and took up a busy life as an actor, musician, art expert at his family’s gallery and, for a few years, weekend racecar driver. He found steady work in the theater and on live dramatic productions that were then a staple of prime-time television.

“There were about 50 of us who were regulars on all those early, live comedies and dramas,” he recalled in 2014, “including Grace Kelly, Eva Marie Saint, Paul Newman, and Robert Redford.”

He appeared opposite Redford and actress Pat Stanley in the original 1961 Broadway production of “Sunday in New York,” a sex farce later made into a popular movie with Jane Fonda and Rod Taylor. (Janis’s role in the film adaptation, as an airline pilot and Lothario, was taken over by Cliff Robertson.)

At the same time, he often worked at his family’s Sidney Janis Gallery, which played a significant part in promoting the work of such mid-century abstract artists as Jackson Pollock, Willem de Kooning, Franz Kline, Robert Motherwell and Mark Rothko. Janis was credited with bringing sculptor Claes Oldenburg and other artists into the gallery’s stable.

As a musician, Janis played trombone as the leader of Conrad Janis and His Tailgate Five and made several recordings. He performed with many jazz stars from an earlier era, including pianist James P. Johnson, clarinetist Edmond Hall, trumpeter Roy Eldridge and drummers Baby Dodds and Jo Jones.

“My agent in New York told me once, ‘Conrad, you have to make up your mind, either the acting or the music,’ ” he said in 1988. “Why do I have to make up my mind?”

Conrad Janis was born Feb. 11, 1928, in New York. His father, Sidney, started out as a vaudeville dancer and later manufactured shirts. The shirt business was so successful that he began to collect and write about modern art with his wife, Harriet. They opened a Manhattan art gallery in the late 1940s and eventually donated more than 100 works, including paintings by Pablo Picasso, Piet Mondrian and Paul Klee, to the Museum of Modern Art.

By the time he was 13, young Conrad was acting regularly onstage and in radio – partly, he said, to avoid school. In fact, he never attended high school and, in his teens, was shuttling between New York and Hollywood. He studied at the Actors Studio workshop in New York and, during the 1950s, was often cast as a drug-addled jazz musician.

“I was always saying, ‘Hey, man, I just got to have a fix,’ ” he said.

He had television roles in “Get Smart,” “Banacek” and “Cannon,” among others, and the airplane disaster movie “Airport 1975” (1974). He later joked that he was in two films named to a list of Hollywood’s 50 worst movies of all time: “Airport 1975” and “That Hagen Girl,” a 1947 drama starring a grown-up Shirley Temple and Ronald Reagan.

Janis and his younger brother, Carroll, became co-owners of the Sidney Janis Gallery after their father’s death in 1989. (Their mother died in 1963.) The brothers had disputes over the gallery’s finances and management and, at one point, filed lawsuits against each other. The gallery closed in 1999.

Janis’s marriages to Vicki Quarles and Ronda Copland ended in divorce. His third wife, actress and screenwriter Maria Grimm, died in 2021. Survivors include two children from his first marriage; his brother; two grandchildren; and two great-grandchildren.

In Los Angeles, Janis led a musical group called the Beverly Hills Unlisted Jazz Band, which rehearsed every Tuesday at his house, appeared in local clubs and at festivals and concerts around the country – including a sold-out engagement at New York’s Carnegie Hall in the late 1970s. Actors who were capable musicians, including Jack Lemmon (piano), George Segal (banjo) and Hal Linden (clarinet), often sat in with the band.

“I like the freedom of expression of jazz, which is much freer than acting,” Janis told the Los Angeles Times in 1988.

“The thing that’s been so great,” he added, “is that I’ve been allowed to do just what I love doing almost all my life. It’s just dumb luck that it worked out that way.”