Dame Alicia Markova, whose ethereal dancing made her one of the 20th century's greatest ballet stars, died Dec. 2 in Bath, England, a day after her 94th birthday. No cause of death was reported.

She either performed with or was mentored by nearly every significant figure in international ballet of the past century, including Anna Pavlova, Sergei Diaghilev, George Balanchine and Frederick Ashton. Miss Markova, who was 5-foot-2, had a regal stage bearing and an unearthly grace that left viewers and critics awestruck.

In spite of her adopted Russian name, Miss Markova was British by birth. The first ballerina from her country with an international following, she was compared to the greatest dancers in history as early as the mid-1930s. Time has only enhanced her stature.

She was the first woman to perform double turns while jumping, prompting one critic to marvel: "It is as though the air were her element, as though no effort were involved in the most difficult of technical feats."

Miss Markova was particularly known for her definitive performances of "Giselle," dancing the role well into her forties, as well as other ballets from the classical repertory, including "Les Sylphides" and "Swan Lake." Beginning in the 1920s, when she was with the legendary Ballets Russes, she also danced modern roles, including many created especially for her.

By the time Miss Markova turned 20, Balanchine and Ashton had choreographed parts for her and composer Igor Stravinsky had taught her how to dance to his syncopated music. She was the first woman to wear a leotard as a costume, with designs painted by Henri Matisse.

In the 1940s, she was described in the New York Times as "the miracle that never fails."

"The more you see her," the American dance critic Edwin Denby wrote, "the higher you value her. In every department of classical technique, she is flawless."

Born Lilian Alicia Marks near London, she was a singularly unpromising and awkward child. She didn't speak until she was 6 and, on a doctor's recommendation, was sent to dancing school to strengthen her frail frame. She showed an immediate aptitude for dance and, when she was 9, was taken to see a performance by Pavlova. Miss Markova received a few private lessons from Pavlova and, as her own career developed, was often likened to the Russian legend for the beauty of her dancing style and for her intense, dark-haired appearance. She occasionally wore Pavlova's jewels in her costumes.

At 14, Miss Markova became the youngest dancer in Ballets Russes, the Russian troupe that revolutionized ballet in the 1920s. Its director, Diaghilev, changed her name from Marks to Markova, reasoning that audiences never would take an English dancer seriously.

After Diaghilev died in 1929, Miss Markova returned to England and a period of penury, when she had to practice in her bathroom. She soon found a position with London's Vic-Wells Ballet, now known as the Royal Ballet, and made her memorable debut in "Giselle" in 1934.

In 1935, she formed a company with Anton Dolin, her principal partner for more than 20 years, performing with audiences so close to the stage that she learned to mask her most difficult moves with a serene, impassive expression. She often gave several performances a day in the 1930s, dancing between features at movie houses, then jumping in a taxi to perform in legitimate ballets. Many of her roles were later danced by Dame Margot Fonteyn, who was Miss Markova's successor as Britain's prima ballerina.

From 1938 to 1941, Miss Markova performed with Leonid Massine's Ballet Russe de Monte Carlo. During World War II, she lived in New York, dancing the forerunner of American Ballet Theatre. In addition to her classical roles, she was renowned for playing the Sugar Plum Fairy in "The Nutcracker," as well as modern roles in Massine's "Rouge et Noir" and in Antony Tudor's "Romeo and Juliet."

Miss Markova, who never married, had a weakness for chocolate and often ate a steak after her performances, yet maintained a steady weight of 98 pounds. She had size-4 feet and wore out two pairs of toe shoes a week. She adored fashion, designed the headpieces she wore on stage and was known to rehearse in a full-length mink coat. ("I was cold," she would protest.)

After returning to England in the 1940s and founding the London Festival Ballet (now the English National Ballet), she continued to perform around the world, seldom faltering in her favorite roles, even well past 40. In 1963, a year after retiring, she was named a dame of the British Empire.

From 1963 to 1969, she directed the Metropolitan Opera Ballet, where she revived the ballet program and taught opera singers how to move on stage. She was a lecturer at the University of Cincinnati from 1970 to 1974 before returning to England. She wrote two books about her life.

She remained a revered figure in ballet and had a phenomenal memory for choreography. In her nineties, she could still re-create, step by step, roles she hadn't danced in more than 50 years.

Survivors include two sisters.

Alicia Markova, shown in 1943, was known for her "flawless" technique.