LOS ANGELES - As a teenager, Esther Williams dreamed of Olympic glory on the U.S. swim team.

She had to settle instead for becoming a movie star.

The self-described "Million Dollar Mermaid," whose wholesome beauty, shapely figure and aquatic skills launched an entire genre of movies - the Technicolor "aqua musicals" - died Thursday at 91. She was remembered for her Hollywood fame but also her influence on fashion and on synchronized swimming, the Olympic sport inspired by her cinematic water ballet.

Williams followed in the footsteps of Sonja Henie - who went from skating champion to movie star - and became one of Hollywood's biggest moneymakers after she lost the chance to compete in the Olympics when they were canceled due to the onset of World War II. She appeared in glittering swimsuit numbers that featured towering fountains, waterfalls, pools, lakes, slides, water skis and anything else that involved water.

"The girl you will dream about!" raved the 1944 trailer for "Bathing Beauty," the first big aqua musical. It showed a smiling Williams posing in a bright pink one-piece suit with the pointy chest popular at the time, a matching pink bow in her hair.

Co-starring Red Skelton, the show was first called "Mr. Coed." But MGM executives changed the title when they realized how big the actress was going to be during filming, according to a biography on Williams' website.

"No one had ever done a swimming movie before," Williams said later. "So we just made it up as we went along. I ad-libbed all my own underwater movements."

That film was followed by many more. "It appeared as if I had invited the audience into the water with me," Williams said, "and it conveyed the sensation that being in there was absolutely delicious."

Such films as "Easy to Wed," ''Neptune's Daughter" and "Dangerous When Wet" all followed the same formula: romance, music, a bit of comedy and a flimsy plot that provided excuses to get Williams in the water.

"They were the ultimate example of Hollywood escapism," says film historian Leonard Maltin. "To their endless credit, the studio seized upon this asset - a beautiful, graceful woman - and figured out a way to make her a movie star."

Williams' film extravaganzas dazzled a second generation via television and the compilation film "That's Entertainment." Her co-stars included the pick of the MGM contract list, including Gene Kelly, Frank Sinatra, Skelton, Ricardo Montalban and Howard Keel.

She also was a favorite swimsuit pinup for GI's in World War II, and a refreshing presence among MGM's stellar gallery - warm, breezy, with a frankness and self-deprecating humor that delighted interviewers.

As news of her death spread Thursday, pinup shots of her circulated on Twitter. Three-time Olympic gold medal-winning swimmer Rowdy Gaines tweeted: "Esther Williams...our first female Michael Phelps...RIP."

USA Synchro, the governing body of U.S. synchronized swimming, also paid tribute. "Her movies with a swimming theme inspired many young girls and women to get into the pool and try to copy her movements," said Judy McGowan, the group's president.

Williams also left her mark on the swimwear industry, popularizing styles that showed just enough cleavage and leg, without being too risque. Her signature suits were colorful, with flattering ruching. She later turned them into a business, forming her own swimwear label.

"Swimwear during that period was all about creating the hourglass shape," says Janie Bryant, a current Hollywood costume designer. "The bust, the waist, the hips. There's been a whole resurgence in the love of vintage and appreciating the hourglass figure that she helped make famous."

The bathing caps also were "decorative and fabulous," said Bryant, who designs for the 1960s-era TV show "Mad Men."

When hard times signaled the end of big studios and costly musicals in the mid-'50s, Williams tried non-swimming roles - with little success. After her 1962 marriage to Fernando Lamas, her co-star in "Dangerous When Wet," she retired from public life.

Lamas' son, actor Lorenzo Lamas, tweeted Thursday: "My stepmom Esther Williams passed peacefully this morning. The best swim teacher and soul mom. RIP."

Esther Jane Williams grew up destined for a career in athletics. She was born Aug. 8, 1921, in Inglewood, a suburb southwest of Los Angeles, one of five children.

A public pool was not far from the modest home where Williams was raised, and it was there that an older sister taught her to swim.

When she was in her teens, the Los Angeles Athletic Club offered to train her four hours a day, aiming for the 1940 Olympic Games at Helsinki. In 1939, she won the Women's Outdoor Nationals title in the 100-meter freestyle, set a record in the 100-meter breaststroke and was a part of several winning relay teams. But the outbreak of war in Europe led to cancellation of the 1940 Olympics, and Williams dropped out of competition to earn a living.

She was selling clothes in a Wilshire Boulevard department store when showman Billy Rose tapped her for a bathing beauty job at the World's Fair in San Francisco.

While there, she was spotted by an MGM producer and an agent. She laughed at the suggestion that she do films that would popularize swimming, as Henie had done with ice skating.

"Frankly I didn't get it," she recalled. "If they had asked me to do some swimming scenes for a star, that would have made sense to me. But to ask me to act was sheer insanity."

She finally agreed to visit MGM boss Louis B. Mayer, and recalled that she took the job after her mother told her: "No one can avoid a challenge in life without breeding regret, and regret is the arsenic of life."

As with Judy Garland, Donna Reed and other stars, Williams was introduced in one of Mickey Rooney's Andy Hardy films, "Andy Hardy's Double Life" (1942).

She also played a small role in "A Guy Named Joe" before "Bathing Beauty" in 1944 began the string of immensely popular musical spectaculars. Among them: "Thrill of a Romance," ''Take Me out to the Ballgame" and "Million Dollar Mermaid" (as Annette Kellerman, an earlier swimming champion turned entertainer).

After leaving MGM, she starred in two Universal dramatic films, "The Unguarded Moment" and "Raw Wind in Eden." Neither was successful. In 1961 Lamas directed her last film, "The Magic Fountain," in Spain. It was never released in America.

When she published her autobiography in 1999, she titled it "The Million Dollar Mermaid."

Lamas was Williams' third husband. Before her fame she was married briefly to a medical student. In 1945 she wed Ben Gage, a radio announcer, and they had three children, Benjamin, Kimball and Susan. They divorced in 1958.

After Lamas' death in 1982, Williams regained the spotlight. Having popularized synchronized swimming with her movies, she was co-host of the event on television at the 1984 Olympic Games in Los Angeles. She issued a video teaching children how to swim and sponsored her own line of swimsuits.

"I've been a lucky lady," she said in a 1984 interview with The Associated Press. "I've had three exciting careers."

Noveck reported from New York. Fashion writer Samantha Critchell in New York and Beth Harris in Los Angeles also contributed to this report.