On Broadway, Orbach starred in hit musicals including "Carnival," "Promises, Promises" (for which he won a Tony Award), "Chicago" and "42nd Street."
Earlier, he was in the original cast of the off-off-Broadway hit "The Fantasticks," playing the narrator. The show went on to run for more than 40 years.
Lights on Broadway marquees were expected to be dimmed for one minute at curtain time Wednesday night in Orbach's memory.
Among his film appearances were roles in "Dirty Dancing," "Prince of the City" and "Crimes and Misdemeanors." In the animated feature "Beauty and the Beast," he voiced the role of the candlestick, and got to sing a key song, "Be Our Guest."
Orbach is expected to appear in early episodes of "Law & Order: Trial by Jury," for which he continued as Briscoe in a secondary role, when the show premieres later this season, Davis said.
"I'm immensely saddened by the passing of not only a friend and colleague, but a legendary figure of 20th century show business," said Dick Wolf, creator and executive producer of the "Law & Order" series, in a statement. "He was one of the most honored performers of his generation. His loss is irreplaceable."
With his hang-dog face and loose-limbed gait, Orbach was adept at playing the street-smart tough guy, but could also hoof and carry a tune. And not only was he a beloved star, he also personified New York's well-worn but implacable edge. A lifelong New Yorker, he inhabited and embodied the Big Apple like few other actors.
Former Mayor Rudolph Giuliani called Orbach "a friend to all New Yorkers" and "a devoted ambassador of the city."
Born in the Bronx in 1935, Orbach was the son of a vaudeville-performer father and a radio-singer mother. He started his acting career in school plays, then attended Northwestern University's prestigious drama school, though he couldn't swing the money to finish. In 1955, he returned to New York to hit the stage.
In a 2000 interview with the Associated Press, Orbach remembered those days fondly. Money was tight, even with his early successes: In 1960 he was earning just $45 a week in "The Fantasticks," but "even married, with a son, we lived all right."
He then began an association with producer David Merrick, appearing in three of Merrick's biggest musical successes, starting in 1961 with "Carnival!", in which he played an embittered puppeteer opposite Anna Maria Alberghetti's winsome Lili.
Orbach won a Tony for his performance in Merrick's "Promises, Promises," the Neil Simon-Burt Bacharach-Hal David musical based on the film "The Apartment." In the show, Orbach played Chuck Baxter, the role originated in the movie by Jack Lemmon.
Yet his biggest hit for Merrick was "42nd Street," which opened on Broadway in 1980 and ran for more than 3,400 performances. In the show, which is based on the c Warner Bros. backstage movie musical, Orbach played hard-boiled producer Julian Marsh, who brings the young hoofer out of the chorus to replace the show's ailing star.
Orbach also was in the original production of "Chicago" in 1975, which also starred Gwen Verdon and Chita Rivera. He played Billy Flynn, the role Richard Gere inherited in the 2002 film.
"It was gift to work with him," recalled actress Brenda Smiley, who co-starred with Orbach in the Off-Broadway stage hit "Scuba Duba," a dark comedy by Bruce Jay Friedman, in 1967-68. "He was a master at that kind of performing and he made it so easy for everyone else."
From early, obscure films like "Cop Hater" and "Mad Dog Coll," Orbach rose to appearances in Woody Allen's "Crimes and Misdemeanors" and the 1981 crime drama "Prince of the City," in a cop role that presaged his "Law & Order" character.
In 1987-88, he starred in the series "The Law and Harry McGraw," a spinoff featuring a character he created in "Murder, She Wrote." It flopped, but five years later he struck gold, following Paul Sorvino as a detective in Manhattan's 27th Precinct.