Still, time cannot wither, nor Botox stale, her infinite hilarity. Both Ms. Rivers' comedy and her life were deeply rooted in self-deprecation and its corollary, self-beautification.
Like the duckling that knows gentlemen prefer swans, Ms. Rivers flapped arms and squawked about it for most of her 81 years. Not only did her convulsive humor win attention, it laid the foundation of a career making fun of people's looks, most often her own. "I knew I was an unwanted baby when I saw my bath toys were a toaster and a radio," kidded the diminutive blonde.
Over a professional life book ended by selling jewelry behind the counter at Wanamaker's and selling costume bijoux on QVC, Ms. Rivers enjoyed multiple, often simultaneous, careers.
The Brooklyn-born and Larchmont-bred Joan Alexandra Molinsky received her college degree from Barnard in 1954, where Margaret Mead was her professor and the drama department her hangout. The following year, Molinsky wed haberdasher James Sanger, a union annulled within six months. Of the failure of her starter marriage, Ms. Rivers blamed her mother. "All she told me was 'The man goes on top and the woman underneath.' So my husband and I slept in bunk beds." In truth, Sanger didn't want children and she did.
She also wanted to act. By day a tour guide at Rockefeller Center, by night, in 1959, she was in Driftwood, an Off-Broadway play that marked both her dramatic debut and that of Barbra Streisand.
Advised to change her name, Ms. Molinsky took the surname of her agent, Tony Rivers.
In 1961 when the Bitter End, the Greenwich Village club, opened its doors, Ms. Rivers performed standup comedy there, crossing paths with Woody Allen, Bill Cosby, and Dick Cavett. The following year, she went to Chicago to work at Second City, the improvisational comedy troupe she considered her finishing school. She returned to New York the following year.
At the time, self-deprecation was a way for women behind the mic to get the audience to laugh with them rather than at them. Ms. Rivers quipped, "My best birth control is just to leave the lights on."
Stand-up did not pay the rent. Through a friend she got a gig writing sketches for the mouse puppet Topo Gigio on The Ed Sullivan Show. She had the mouse ask Sullivan to explain football. "Topo Gigio paid my car payments for six months," she said.
In 1965, when Ms. Rivers made her debut on The Tonight Show with Johnny Carson, the host gave her the comedy equivalent of papal benediction. After she performed a sidesplitting act about beauty vs. brains in women, Carson beckoned her to the couch next to his desk. He reassured her that men really do like smart women. "No man ever put his hand up a woman's dress looking for her library card," Rivers retorted. She became a Tonight Show regular, and permanent guest host in 1983, where her catchphrase became "Can we talk?"
If Carson gave Ms. Rivers comedy credibility, then Ed Sullivan conferred upon her America's adoration.
With a routine about her jealousy of beautiful looking, empty-headed women, she cracked up the stone-faced Sullivan and the audience. Over the next five years, she would be on his show 21 times. The tenor of her act was much like one 1967 Sullivan performance in which she summed up the difference between women and men: "A girl, unmarried, 30 years old - an old maid; a man, unmarried, 90 years old - a catch!
By this time, she was married. She met producer Edgar Rosenberg in 1965, and they wed four days later. He became her manager, and they had a daughter, Melissa, in 1968.
Between 1968 and 1986, you couldn't turn on a television in America without seeing Ms. Rivers. The Hollywood Squares. The Carol Burnett Show. The Tonight Show. Opening for Robert Goulet and Helen Reddy in Vegas. She had the country in stitches, even if her fat-shaming of Elizabeth Taylor - "She has more chins than the Chinese telephone directory!" - made some wince.
Ms. Rivers' extracurricular work developed her fantasies. Her 1973 teleplay The Girl Most Likely To . . . starred Stockard Channing as a homely girl made beautiful by facial reconstruction after a car crash. Ms. Rivers wrote and directed the 1978 film Rabbit Test, starring Billy Crystal as the first pregnant man.
When Fox network offered Ms. Rivers her own late-night show (to be produced by her husband) slated to run against The Tonight Show, in 1986, she jumped at it. Carson was furious that he had to hear the news from Fox and never again spoke to his protégée. Months later, Fox executives wanted to fire Rosenberg, and Ms. Rivers challenged them, leading the network to fire both of them. In 1987, Rosenberg committed suicide at Philadelphia's Four Seasons Hotel, leaving farewell audiotapes for his wife and his daughter, who at the time was a student at the University of Pennsylvania.
Jobless, widowed, and blackballed by NBC ( The Tonight Show's network), Ms. Rivers slowly made her way back. In 1989, she established her own daytime gabfest, The Joan Rivers Show, which ran through 1994 and earned her a daytime Emmy for Outstanding Host in 1990.
Her follow-up was the part of a lifetime: Long influenced by the profane comedy of Lenny Bruce, Ms. Rivers played his mother on Broadway in Sally Marr . . . and Her Escorts. She may not have won over reviewers, but she was nominated for a Tony Award.
Times were changing, and Ms. Rivers attracted a new audience, creating a community of snark with her daughter as they cohosted fashion color analysis from the red carpet on the E! channel. (2014 sample: When Madonna arrived at the 2014 Grammys wearing a black suit and wide-brimmed hat, Ms. Rivers cracked: "She looks like the world's meanest rabbi!")
By the beginning of her last decade, even her former manager Billy Sammeth said in the 2010 documentary, Joan Rivers: A Piece of Work, "People now see her as a plastic surgery addict who's past her sell-by date."
Musing over The End recently, Ms. Rivers had said, "God always comes up with a third-act twist - and we don't know until we die whether it was a tragedy or a comedy."
Ms. Rivers is survived by her daughter, her grandson, and comedians such as Kathy Griffin, Chelsea Handler, Sarah Silverman and Whitney Cummings, whose careers she made possible.